diff mercurial/revlogutils/constants.py @ 46857:cc65cea90edb

revlog: move the details of revlog "v1" index inside revlog.utils.constants

The revlog module is quite large and this kind of format information would handy
for other module. So let us start to gather this information about the format in
a more appropriate place.

We update various reference to this information to use the new "source of truth"
in the process.

Differential Revision: https://phab.mercurial-scm.org/D10304

--- a/mercurial/revlogutils/constants.py	Mon Apr 05 12:20:52 2021 +0200
+++ b/mercurial/revlogutils/constants.py	Mon Apr 05 12:21:01 2021 +0200
@@ -44,6 +44,19 @@
 # 20 bytes: nodeid
 INDEX_ENTRY_V0 = struct.Struct(b">4l20s20s20s")
 
+## index v1
+#  6 bytes: offset
+#  2 bytes: flags
+#  4 bytes: compressed length
+#  4 bytes: uncompressed length
+#  4 bytes: base rev
+#  4 bytes: link rev
+#  4 bytes: parent 1 rev
+#  4 bytes: parent 2 rev
+# 32 bytes: nodeid
+INDEX_ENTRY_V1 = struct.Struct(b">Qiiiiii20s12x")
+assert INDEX_ENTRY_V1.size == 32 * 2
+
 # revlog index flags
 
 # For historical reasons, revlog's internal flags were exposed via the