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[PATCH v2 03/15] hash: use uint32_t for object_id algorithm

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
Nov 17, 2025, 22:16 UTC
Message-ID
<20251117221621.2863243-4-sandals@crustytoothpaste.net>
In-Reply-To
<20251117221621.2863243-1-sandals@crustytoothpaste.net>

We currently use an int for this value, but we'll define this structure from Rust in a future commit and we want to ensure that our data types are exactly identical. To make that possible, use a uint32_t for the hash algorithm.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 hash.c       |  6 +++---
 hash.h       | 10 +++++-----
 oidtree.c    |  2 +-
 repository.c |  6 +++---
 repository.h |  4 ++--
 serve.c      |  2 +-
 6 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/hash.c b/hash.c
index 4a04ecb50e..81b4f87027 100644
--- a/hash.c
+++ b/hash.c
@@ -241,7 +241,7 @@ const char *empty_tree_oid_hex(const struct git_hash_algo *algop)
 	return oid_to_hex_r(buf, algop->empty_tree);
 }
 
-int hash_algo_by_name(const char *name)
+uint32_t hash_algo_by_name(const char *name)
 {
 	if (!name)
 		return GIT_HASH_UNKNOWN;
@@ -251,7 +251,7 @@ int hash_algo_by_name(const char *name)
 	return GIT_HASH_UNKNOWN;
 }
 
-int hash_algo_by_id(uint32_t format_id)
+uint32_t hash_algo_by_id(uint32_t format_id)
 {
 	for (size_t i = 1; i < GIT_HASH_NALGOS; i++)
 		if (format_id == hash_algos[i].format_id)
@@ -259,7 +259,7 @@ int hash_algo_by_id(uint32_t format_id)
 	return GIT_HASH_UNKNOWN;
 }
 
-int hash_algo_by_length(size_t len)
+uint32_t hash_algo_by_length(size_t len)
 {
 	for (size_t i = 1; i < GIT_HASH_NALGOS; i++)
 		if (len == hash_algos[i].rawsz)
diff --git a/hash.h b/hash.h
index fae966b23c..99c9c2a0a8 100644
--- a/hash.h
+++ b/hash.h
@@ -211,7 +211,7 @@ static inline void git_SHA256_Clone(git_SHA256_CTX *dst, const git_SHA256_CTX *s
 
 struct object_id {
 	unsigned char hash[GIT_MAX_RAWSZ];
-	int algo;	/* XXX requires 4-byte alignment */
+	uint32_t algo;	/* XXX requires 4-byte alignment */
 };
 
 #define GET_OID_QUIETLY                  01
@@ -344,13 +344,13 @@ static inline void git_hash_final_oid(struct object_id *oid, struct git_hash_ctx
  * Return a GIT_HASH_* constant based on the name.  Returns GIT_HASH_UNKNOWN if
  * the name doesn't match a known algorithm.
  */
-int hash_algo_by_name(const char *name);
+uint32_t hash_algo_by_name(const char *name);
 /* Identical, except based on the format ID. */
-int hash_algo_by_id(uint32_t format_id);
+uint32_t hash_algo_by_id(uint32_t format_id);
 /* Identical, except based on the length. */
-int hash_algo_by_length(size_t len);
+uint32_t hash_algo_by_length(size_t len);
 /* Identical, except for a pointer to struct git_hash_algo. */
-static inline int hash_algo_by_ptr(const struct git_hash_algo *p)
+static inline uint32_t hash_algo_by_ptr(const struct git_hash_algo *p)
 {
 	size_t i;
 	for (i = 0; i < GIT_HASH_NALGOS; i++) {
diff --git a/oidtree.c b/oidtree.c
index 151568f74f..324de94934 100644
--- a/oidtree.c
+++ b/oidtree.c
@@ -10,7 +10,7 @@ struct oidtree_iter_data {
 	oidtree_iter fn;
 	void *arg;
 	size_t *last_nibble_at;
-	int algo;
+	uint32_t algo;
 	uint8_t last_byte;
 };
 
diff --git a/repository.c b/repository.c
index 186d2c1028..ebe719de3c 100644
--- a/repository.c
+++ b/repository.c
@@ -39,7 +39,7 @@ struct repository *the_repository = &the_repo;
 static void set_default_hash_algo(struct repository *repo)
 {
 	const char *hash_name;
-	int algo;
+	uint32_t algo;
 
 	hash_name = getenv("GIT_TEST_DEFAULT_HASH_ALGO");
 	if (!hash_name)
@@ -186,12 +186,12 @@ void repo_set_gitdir(struct repository *repo,
 			repo->gitdir, "index");
 }
 
-void repo_set_hash_algo(struct repository *repo, int hash_algo)
+void repo_set_hash_algo(struct repository *repo, uint32_t hash_algo)
 {
 	repo->hash_algo = &hash_algos[hash_algo];
 }
 
-void repo_set_compat_hash_algo(struct repository *repo MAYBE_UNUSED, int algo)
+void repo_set_compat_hash_algo(struct repository *repo MAYBE_UNUSED, uint32_t algo)
 {
 #ifdef WITH_RUST
 	if (hash_algo_by_ptr(repo->hash_algo) == algo)
diff --git a/repository.h b/repository.h
index 5808a5d610..c0a3543b24 100644
--- a/repository.h
+++ b/repository.h
@@ -193,8 +193,8 @@ struct set_gitdir_args {
 void repo_set_gitdir(struct repository *repo, const char *root,
 		     const struct set_gitdir_args *extra_args);
 void repo_set_worktree(struct repository *repo, const char *path);
-void repo_set_hash_algo(struct repository *repo, int algo);
-void repo_set_compat_hash_algo(struct repository *repo, int compat_algo);
+void repo_set_hash_algo(struct repository *repo, uint32_t algo);
+void repo_set_compat_hash_algo(struct repository *repo, uint32_t compat_algo);
 void repo_set_ref_storage_format(struct repository *repo,
 				 enum ref_storage_format format);
 void initialize_repository(struct repository *repo);
diff --git a/serve.c b/serve.c
index 53ecab3b42..49a6e39b1d 100644
--- a/serve.c
+++ b/serve.c
@@ -14,7 +14,7 @@
 
 static int advertise_sid = -1;
 static int advertise_object_info = -1;
-static int client_hash_algo = GIT_HASH_SHA1_LEGACY;
+static uint32_t client_hash_algo = GIT_HASH_SHA1_LEGACY;
 
 static int always_advertise(struct repository *r UNUSED,
 			    struct strbuf *value UNUSED)
Previous: brian m. carlsonNext: brian m. carlson
Message 88 of 118 in “SHA-1/SHA-256 interoperability, part 2”
  1. 00/14 SHA-1/SHA-256 interoperability, part 2brian m. carlson, Oct 27, 2025
  2. 14/14 object-file-convert: always make sure object ID algo is validbrian m. carlson, Oct 27, 2025
  3. 05/14 rust: add a hash algorithm abstractionbrian m. carlson, Oct 27, 2025
  4. Patrick SteinhardtOct 28, 2025
  5. Ezekiel NewrenOct 28, 2025
  6. Junio C HamanoOct 28, 2025
  7. Ezekiel NewrenOct 28, 2025
  8. Junio C HamanoOct 29, 2025
  9. Junio C HamanoOct 29, 2025
  10. 11/14 rust: add functionality to hash an objectbrian m. carlson, Oct 27, 2025
  11. Patrick SteinhardtOct 28, 2025
  12. brian m. carlsonOct 29, 2025
  13. Patrick SteinhardtOct 29, 2025
  14. Ezekiel NewrenOct 28, 2025
  15. brian m. carlsonOct 29, 2025
  16. Ben KnobleOct 29, 2025
  17. 07/14 csum-file: define hashwrite's count as a uint32_tbrian m. carlson, Oct 27, 2025
  18. Ezekiel NewrenOct 28, 2025
  19. 09/14 hash: expose hash context functions to Rustbrian m. carlson, Oct 27, 2025
  20. Junio C HamanoOct 29, 2025
  21. brian m. carlsonOct 30, 2025
  22. Junio C HamanoOct 30, 2025
  23. 13/14 rust: add a small wrapper around the hashfile codebrian m. carlson, Oct 27, 2025
  24. Ezekiel NewrenOct 28, 2025
  25. brian m. carlsonOct 29, 2025
  26. 06/14 hash: add a function to look up hash algo structsbrian m. carlson, Oct 27, 2025
  27. Patrick SteinhardtOct 28, 2025
  28. Junio C HamanoOct 28, 2025
  29. brian m. carlsonNov 4, 2025
  30. Junio C HamanoNov 4, 2025
  31. 10/14 rust: add a build.rs script for testsbrian m. carlson, Oct 27, 2025
  32. Patrick SteinhardtOct 28, 2025
  33. Ezekiel NewrenOct 28, 2025
  34. Junio C HamanoOct 29, 2025
  35. Ezekiel NewrenOct 29, 2025
  36. Junio C HamanoOct 29, 2025
  37. Patrick SteinhardtOct 30, 2025
  38. Junio C HamanoOct 30, 2025
  39. Ezekiel NewrenOct 31, 2025
  40. Junio C HamanoNov 1, 2025
  41. 12/14 rust: add a new binary loose object map formatbrian m. carlson, Oct 27, 2025
  42. Patrick SteinhardtOct 28, 2025
  43. brian m. carlsonOct 29, 2025
  44. Patrick SteinhardtOct 29, 2025
  45. Junio C HamanoOct 29, 2025
  46. Junio C HamanoOct 29, 2025
  47. 08/14 write-or-die: add an fsync component for the loose object mapbrian m. carlson, Oct 27, 2025
  48. 02/14 conversion: don't crash when no destination algobrian m. carlson, Oct 27, 2025
  49. 03/14 hash: use uint32_t for object_id algorithmbrian m. carlson, Oct 27, 2025
  50. Patrick SteinhardtOct 28, 2025
  51. Ezekiel NewrenOct 28, 2025
  52. Junio C HamanoOct 28, 2025
  53. Ezekiel NewrenOct 28, 2025
  54. Junio C HamanoOct 28, 2025
  55. brian m. carlsonOct 30, 2025
  56. Collin FunkOct 30, 2025
  57. brian m. carlsonNov 3, 2025
  58. brian m. carlsonOct 29, 2025
  59. Patrick SteinhardtOct 29, 2025
  60. 04/14 rust: add a ObjectID structbrian m. carlson, Oct 27, 2025
  61. Patrick SteinhardtOct 28, 2025
  62. Ezekiel NewrenOct 28, 2025
  63. brian m. carlsonOct 29, 2025
  64. Junio C HamanoOct 28, 2025
  65. brian m. carlsonOct 29, 2025
  66. brian m. carlsonOct 29, 2025
  67. Patrick SteinhardtOct 29, 2025
  68. brian m. carlsonOct 30, 2025
  69. 01/14 repository: require Rust support for interoperabilitybrian m. carlson, Oct 27, 2025
  70. Patrick SteinhardtOct 28, 2025
  71. Junio C HamanoOct 29, 2025
  72. Junio C HamanoOct 29, 2025
  73. Ezekiel NewrenNov 11, 2025
  74. Junio C HamanoNov 14, 2025
  75. Junio C HamanoNov 14, 2025
  76. Junio C HamanoNov 17, 2025
  77. brian m. carlsonNov 17, 2025
  78. Junio C HamanoNov 18, 2025
  79. brian m. carlsonNov 19, 2025
  80. Junio C HamanoNov 19, 2025
  81. Ezekiel NewrenNov 19, 2025
  82. Ezekiel NewrenNov 20, 2025
  83. brian m. carlsonNov 20, 2025
  84. Ezekiel NewrenNov 20, 2025
  85. Junio C HamanoNov 20, 2025
  86. 00/15 SHA-1/SHA-256 interoperability, part 2brian m. carlson, Nov 17, 2025
  87. 02/15 conversion: don't crash when no destination algobrian m. carlson, Nov 17, 2025
  88. 03/15 hash: use uint32_t for object_id algorithmbrian m. carlson, Nov 17, 2025
  89. 01/15 repository: require Rust support for interoperabilitybrian m. carlson, Nov 17, 2025
  90. 04/15 rust: add a ObjectID structbrian m. carlson, Nov 17, 2025
  91. 06/15 hash: add a function to look up hash algo structsbrian m. carlson, Nov 17, 2025
  92. 08/15 csum-file: define hashwrite's count as a uint32_tbrian m. carlson, Nov 17, 2025
  93. 05/15 rust: add a hash algorithm abstractionbrian m. carlson, Nov 17, 2025
  94. 09/15 write-or-die: add an fsync component for the object mapbrian m. carlson, Nov 17, 2025
  95. 10/15 hash: expose hash context functions to Rustbrian m. carlson, Nov 17, 2025
  96. 07/15 rust: add additional helpers for ObjectIDbrian m. carlson, Nov 17, 2025
  97. 12/15 rust: add functionality to hash an objectbrian m. carlson, Nov 17, 2025
  98. 11/15 rust: add a build.rs script for testsbrian m. carlson, Nov 17, 2025
  99. 14/15 rust: add a small wrapper around the hashfile codebrian m. carlson, Nov 17, 2025
  100. 15/15 object-file-convert: always make sure object ID algo is validbrian m. carlson, Nov 17, 2025
  101. 13/15 rust: add a new binary object map formatbrian m. carlson, Nov 17, 2025
  102. 00/16 SHA-1/SHA-256 interoperability, part 2brian m. carlson, Feb 7, 2026
  103. 04/16 rust: add a ObjectID structbrian m. carlson, Feb 7, 2026
  104. 02/16 conversion: don't crash when no destination algobrian m. carlson, Feb 7, 2026
  105. 01/16 repository: require Rust support for interoperabilitybrian m. carlson, Feb 7, 2026
  106. 03/16 hash: use uint32_t for object_id algorithmbrian m. carlson, Feb 7, 2026
  107. 07/16 rust: add additional helpers for ObjectIDbrian m. carlson, Feb 7, 2026
  108. 14/16 rust: add a new binary object map formatbrian m. carlson, Feb 7, 2026
  109. 08/16 csum-file: define hashwrite's count as a uint32_tbrian m. carlson, Feb 7, 2026
  110. 06/16 hash: add a function to look up hash algo structsbrian m. carlson, Feb 7, 2026
  111. 11/16 rust: fix linking binaries with cargobrian m. carlson, Feb 7, 2026
  112. 12/16 rust: add a build.rs script for testsbrian m. carlson, Feb 7, 2026
  113. 10/16 hash: expose hash context functions to Rustbrian m. carlson, Feb 7, 2026
  114. 05/16 rust: add a hash algorithm abstractionbrian m. carlson, Feb 7, 2026
  115. 09/16 write-or-die: add an fsync component for the object mapbrian m. carlson, Feb 7, 2026
  116. 13/16 rust: add functionality to hash an objectbrian m. carlson, Feb 7, 2026
  117. 15/16 rust: add a small wrapper around the hashfile codebrian m. carlson, Feb 7, 2026
  118. 16/16 object-file-convert: always make sure object ID algo is validbrian m. carlson, Feb 7, 2026

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