Merge pull request facebook#1384 from ulikunitz/dev

Clarify special case of offset history update
terrelln · Oct 23, 2018 · 059aa1b · 059aa1b
2 parents ca46afd + f0fe9b0
commit 059aa1b
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/doc/zstd_compression_format.md b/doc/zstd_compression_format.md
@@ -919,6 +919,10 @@ This means that when `Repeated_Offset1` (most recent) is used, history is unmodi
 When `Repeated_Offset2` is used, it's swapped with `Repeated_Offset1`.
 If any other offset is used, it becomes `Repeated_Offset1` and the rest are shift back by one.
 
+In the case of an `offset_value` of 3 and the literal length of the current
+sequence is zero the value `Repeated_Offset1 - 1_byte` is a new offset,
+becoming the lead of the offset history and the first two repeated offsets will
+be shifted back.
 
 Skippable Frames
 ----------------