Scan all rows of each row group, fixes #32

Author: brunchboy

CHANGELOG.md

@@ -6,7 +6,9 @@ This change log follows the conventions of
 
 ## [Unreleased][unreleased]
 
-Nothing so far.
+### Fixed
+
+- An error in interpreting a value in the database export file format could lead to some rows that were actually present in tables not being found. Thanks to [@IvanOnishchenko](https://github.com/IvanOnishchenko) for [pointing this out](https://github.com/Deep-Symmetry/crate-digger/issues/32).
 
 ## [0.2.0] - 2024-05-04
 

doc/modules/ROOT/pages/exports.adoc

@@ -255,6 +255,8 @@ playlist entries) have a lot of very small rows, too many to count
 with a single byte. But then why not just always use
 __num_rows_large__?
 
+NOTE: The row counter entries represent the number of actually-present rows in the page. To find them, you need to scan all 16 entries of each of the row groups present in the page, ignoring any whose <<#row-presence-bits,row presence bit>> is zero.
+
 The purpose of the next two bytes are is also unclear. Of _u~3~_ Mr.
 Flesniak said “a bitmask (first track: 32)”, and he described _u~4~_
 as “often 0, sometimes larger, especially for pages with a high number
@@ -296,6 +298,7 @@ deleted). The number of row index entries is determined, as described
 above, by the value of either __num_rows_small__ or
 __num_rows_large__.
 
+[#row-presence-bits]
 The bit mask for the first group of up to sixteen rows, labeled
 _row~pf0~_ in the diagram (meaning “row presence flags group 0”), is
 found near the end of the page. The last two bytes after each row

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>org.deepsymmetry</groupId>
     <artifactId>crate-digger</artifactId>
-    <version>0.2.0</version>
+    <version>0.2.1-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>Crate Digger</name>

src/main/kaitai/rekordbox_pdb.ksy

@@ -286,7 +286,7 @@ types:
       rows:
         type: row_ref(_index)
         repeat: expr
-        repeat-expr: '(group_index < (_parent.num_row_groups - 1)) ? 16 : ((_parent.num_rows - 1) % 16 + 1)'
+        repeat-expr: 16
         doc: |
           The row offsets in this group.