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[PATCH 5/5] commit-graph-format.txt: fix "Hash Version" description

From
MÅMartin Ågren <martin.agren@gmail.com>
Date
Aug 14, 2020, 12:21 UTC
Message-ID
<bbcd97db8a2c94343950bb0cf8cbd5c9c01b4577.1597406877.git.martin.agren@gmail.com>
In-Reply-To
<cover.1597406877.git.martin.agren@gmail.com>

We say that value 1 means "SHA-1", but in fact, it means "whatever the_hash_algo is", see commit c166599862 ("commit-graph: convert to using the_hash_algo", 2018-11-14).

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
---
 If we want to be more fine-grained in the future, we'll need to say,
 e.g., "2 means SHA-1, 3 means SHA-256" or, perhaps preferrably, bump the
 version number.
 I wonder: Should we instead say "1 means SHA-1, 2 means SHA-256"? It
 could be implemented as "easily" as "if (value_from_header !=
 value_from_the_hash_algo) die(...);" for now. Might that pay off in the
 long run?
 This relates to Stolee's "in a vacuum" comment [1] ... so maybe we're
 fine.
 [1] https://lore.kernel.org/git/da077fb0-14bb-b84f-c526-d759ebc9f5eb@gmail.com/
 Documentation/technical/commit-graph-format.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/technical/commit-graph-format.txt b/Documentation/technical/commit-graph-format.txt
index 440541045d..3535426d32 100644
--- a/Documentation/technical/commit-graph-format.txt
+++ b/Documentation/technical/commit-graph-format.txt
@@ -42,8 +42,8 @@ HEADER:
   1-byte version number:
       Currently, the only valid version is 1.
 
-  1-byte Hash Version (1 = SHA-1)
-      We infer the hash length (H) from this value.
+  1-byte Hash Version (1 = SHA-1 in SHA-1 repo, SHA-256 in SHA-256 repo)
+      We infer the hash length (H) from the hash algo derived from this value.
 
   1-byte number (C) of "chunks"
 
-- 
2.28.0.277.g9b3c35fffd
Previous: Junio C HamanoNext: Derrick Stolee
Message 24 of 35 in “Documentation updates for SHA-256”
  1. 0/2 Documentation updates for SHA-256brian m. carlson, Aug 13, 2020
  2. 1/2 docs: document SHA-256 pack and indicesbrian m. carlson, Aug 13, 2020
  3. Derrick StoleeAug 14, 2020
  4. 2/2 docs: fix step in transition planbrian m. carlson, Aug 13, 2020
  5. Martin ÅgrenAug 14, 2020
  6. Derrick StoleeAug 14, 2020
  7. Junio C HamanoAug 14, 2020
  8. brian m. carlsonAug 14, 2020
  9. Junio C HamanoAug 14, 2020
  10. 0/5 more SHA-256 documentationMartin Ågren, Aug 14, 2020
  11. 1/5 http-protocol.txt: document SHA-256 "want"/"have" formatMartin Ågren, Aug 14, 2020
  12. Junio C HamanoAug 14, 2020
  13. brian m. carlsonAug 14, 2020
  14. Martin ÅgrenAug 14, 2020
  15. Junio C HamanoAug 14, 2020
  16. Junio C HamanoAug 14, 2020
  17. 4/5 shallow.txt: document SHA-256 shallow formatMartin Ågren, Aug 14, 2020
  18. 3/5 protocol-capabilities.txt: clarify "allow-x-sha1-in-want" re SHA-256Martin Ågren, Aug 14, 2020
  19. Derrick StoleeAug 14, 2020
  20. Martin ÅgrenAug 14, 2020
  21. Junio C HamanoAug 14, 2020
  22. Martin ÅgrenAug 14, 2020
  23. Junio C HamanoAug 14, 2020
  24. 5/5 commit-graph-format.txt: fix "Hash Version" descriptionMartin Ågren, Aug 14, 2020
  25. Derrick StoleeAug 14, 2020
  26. Martin ÅgrenAug 14, 2020
  27. 2/5 index-format.txt: document SHA-256 index formatMartin Ågren, Aug 14, 2020
  28. Derrick StoleeAug 14, 2020
  29. Martin ÅgrenAug 14, 2020
  30. brian m. carlsonAug 14, 2020
  31. 0/4 more SHA-256 documentationMartin Ågren, Aug 15, 2020
  32. 2/4 index-format.txt: document SHA-256 index formatMartin Ågren, Aug 15, 2020
  33. 3/4 protocol-capabilities.txt: clarify "allow-x-sha1-in-want" re SHA-256Martin Ågren, Aug 15, 2020
  34. 4/4 shallow.txt: document SHA-256 shallow formatMartin Ågren, Aug 15, 2020
  35. 1/4 http-protocol.txt: document SHA-256 "want"/"have" formatMartin Ågren, Aug 15, 2020

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