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[PATCH v5 5/8] sha1: do not redefine `platform_SHA_CTX` and friends

From
Taylor Blau <me@ttaylorr.com>
Date
Sep 26, 2024, 15:22 UTC
Message-ID
<9913a5d971389e7e657ea151eaedc94bf025f3fc.1727364141.git.me@ttaylorr.com>
In-Reply-To
<cover.1727364141.git.me@ttaylorr.com>

Our in-tree SHA-1 wrappers all define platform_SHA_CTX and related macros to point at the opaque "context" type, init, update, and similar functions for each specific implementation.

In hash.h, we use these platform_ variables to set up the function pointers for, e.g., the_hash_algo->init_fn(), etc.

But while these header files have a header-specific macro that prevents them declaring their structs / functions multiple times, they unconditionally define the platform variables, making it impossible to load multiple SHA-1 implementations at once.

As a prerequisite for loading a separate SHA-1 implementation for non-cryptographic uses, only define the platform_ variables if they have not already been defined.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 block-sha1/sha1.h | 2 ++
 sha1/openssl.h    | 2 ++
 sha1dc_git.h      | 3 +++
 3 files changed, 7 insertions(+)
diff --git a/block-sha1/sha1.h b/block-sha1/sha1.h
index 9fb0441b98..47bb916636 100644
--- a/block-sha1/sha1.h
+++ b/block-sha1/sha1.h
@@ -16,7 +16,9 @@ void blk_SHA1_Init(blk_SHA_CTX *ctx);
 void blk_SHA1_Update(blk_SHA_CTX *ctx, const void *dataIn, size_t len);
 void blk_SHA1_Final(unsigned char hashout[20], blk_SHA_CTX *ctx);
 
+#ifndef platform_SHA_CTX
 #define platform_SHA_CTX	blk_SHA_CTX
 #define platform_SHA1_Init	blk_SHA1_Init
 #define platform_SHA1_Update	blk_SHA1_Update
 #define platform_SHA1_Final	blk_SHA1_Final
+#endif
diff --git a/sha1/openssl.h b/sha1/openssl.h
index 006c1f4ba5..1038af47da 100644
--- a/sha1/openssl.h
+++ b/sha1/openssl.h
@@ -40,10 +40,12 @@ static inline void openssl_SHA1_Clone(struct openssl_SHA1_CTX *dst,
 	EVP_MD_CTX_copy_ex(dst->ectx, src->ectx);
 }
 
+#ifndef platform_SHA_CTX
 #define platform_SHA_CTX openssl_SHA1_CTX
 #define platform_SHA1_Init openssl_SHA1_Init
 #define platform_SHA1_Clone openssl_SHA1_Clone
 #define platform_SHA1_Update openssl_SHA1_Update
 #define platform_SHA1_Final openssl_SHA1_Final
+#endif
 
 #endif /* SHA1_OPENSSL_H */
diff --git a/sha1dc_git.h b/sha1dc_git.h
index 60e3ce8439..f6f880cabe 100644
--- a/sha1dc_git.h
+++ b/sha1dc_git.h
@@ -18,7 +18,10 @@ void git_SHA1DCFinal(unsigned char [20], SHA1_CTX *);
 void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *data, unsigned long len);
 
 #define platform_SHA_IS_SHA1DC /* used by "test-tool sha1-is-sha1dc" */
+
+#ifndef platform_SHA_CTX
 #define platform_SHA_CTX SHA1_CTX
 #define platform_SHA1_Init git_SHA1DCInit
 #define platform_SHA1_Update git_SHA1DCUpdate
 #define platform_SHA1_Final git_SHA1DCFinal
+#endif
-- 
2.46.1.507.gffd0c9a15b2.dirty
Previous: Taylor BlauNext: Taylor Blau
Message 93 of 99 in “hash.h: support choosing a separate SHA-1 for non-cryptographic uses”
  1. 0/4 hash.h: support choosing a separate SHA-1 for non-cryptographic usesTaylor Blau, Sep 1, 2024
  2. 1/4 sha1: do not redefine `platform_SHA_CTX` and friendsTaylor Blau, Sep 1, 2024
  3. Patrick SteinhardtSep 2, 2024
  4. Taylor BlauSep 3, 2024
  5. 2/4 hash.h: scaffolding for _fast hashing variantsTaylor Blau, Sep 1, 2024
  6. Patrick SteinhardtSep 2, 2024
  7. Junio C HamanoSep 3, 2024
  8. Taylor BlauSep 3, 2024
  9. Junio C HamanoSep 3, 2024
  10. Taylor BlauSep 3, 2024
  11. Patrick SteinhardtSep 4, 2024
  12. Junio C HamanoSep 4, 2024
  13. Taylor BlauSep 3, 2024
  14. 3/4 Makefile: allow specifying a SHA-1 for non-cryptographic usesTaylor Blau, Sep 1, 2024
  15. Patrick SteinhardtSep 2, 2024
  16. Taylor BlauSep 3, 2024
  17. 4/4 csum-file.c: use fast SHA-1 implementation when availableTaylor Blau, Sep 1, 2024
  18. Patrick SteinhardtSep 2, 2024
  19. brian m. carlsonSep 3, 2024
  20. Taylor BlauSep 3, 2024
  21. Junio C HamanoSep 2, 2024
  22. Taylor BlauSep 3, 2024
  23. Junio C HamanoSep 3, 2024
  24. brian m. carlsonSep 2, 2024
  25. Taylor BlauSep 3, 2024
  26. Junio C HamanoSep 3, 2024
  27. brian m. carlsonSep 4, 2024
  28. Jeff KingSep 5, 2024
  29. Junio C HamanoSep 5, 2024
  30. Taylor BlauSep 5, 2024
  31. Junio C HamanoSep 5, 2024
  32. Taylor BlauSep 5, 2024
  33. Taylor BlauSep 5, 2024
  34. Taylor BlauSep 5, 2024
  35. Jeff KingSep 5, 2024
  36. Junio C HamanoSep 5, 2024
  37. 0/4 hash.h: support choosing a separate SHA-1 for non-cryptographic usesTaylor Blau, Sep 5, 2024
  38. 1/4 sha1: do not redefine `platform_SHA_CTX` and friendsTaylor Blau, Sep 5, 2024
  39. 2/4 hash.h: scaffolding for _fast hashing variantsTaylor Blau, Sep 5, 2024
  40. 3/4 Makefile: allow specifying a SHA-1 for non-cryptographic usesTaylor Blau, Sep 5, 2024
  41. 4/4 csum-file.c: use fast SHA-1 implementation when availableTaylor Blau, Sep 5, 2024
  42. 0/9 hash.h: support choosing a separate SHA-1 for non-cryptographic usesTaylor Blau, Sep 6, 2024
  43. 1/9 finalize_object_file(): check for name collision before renamingTaylor Blau, Sep 6, 2024
  44. 2/9 finalize_object_file(): refactor unlink_or_warn() placementTaylor Blau, Sep 6, 2024
  45. 3/9 finalize_object_file(): implement collision checkTaylor Blau, Sep 6, 2024
  46. Junio C HamanoSep 6, 2024
  47. Chris TorekSep 6, 2024
  48. Jeff KingSep 10, 2024
  49. Junio C HamanoSep 10, 2024
  50. Patrick SteinhardtSep 16, 2024
  51. Taylor BlauSep 16, 2024
  52. Taylor BlauSep 16, 2024
  53. Junio C HamanoSep 17, 2024
  54. 4/9 pack-objects: use finalize_object_file() to rename pack/idx/etcTaylor Blau, Sep 6, 2024
  55. 5/9 i5500-git-daemon.sh: use compile-able version of Git without OpenSSLTaylor Blau, Sep 6, 2024
  56. Jeff KingSep 11, 2024
  57. Jeff KingSep 11, 2024
  58. Junio C HamanoSep 12, 2024
  59. Junio C HamanoSep 11, 2024
  60. Jeff KingSep 11, 2024
  61. 6/9 sha1: do not redefine `platform_SHA_CTX` and friendsTaylor Blau, Sep 6, 2024
  62. 7/9 hash.h: scaffolding for _fast hashing variantsTaylor Blau, Sep 6, 2024
  63. 8/9 Makefile: allow specifying a SHA-1 for non-cryptographic usesTaylor Blau, Sep 6, 2024
  64. 9/9 csum-file.c: use fast SHA-1 implementation when availableTaylor Blau, Sep 6, 2024
  65. Junio C HamanoSep 6, 2024
  66. 0/8 hash.h: support choosing a separate SHA-1 for non-cryptographic usesTaylor Blau, Sep 24, 2024
  67. 1/8 finalize_object_file(): check for name collision before renamingTaylor Blau, Sep 24, 2024
  68. Junio C HamanoSep 25, 2024
  69. 2/8 finalize_object_file(): refactor unlink_or_warn() placementTaylor Blau, Sep 24, 2024
  70. 3/8 finalize_object_file(): implement collision checkTaylor Blau, Sep 24, 2024
  71. Jeff KingSep 24, 2024
  72. Taylor BlauSep 24, 2024
  73. Jeff KingSep 24, 2024
  74. Taylor BlauSep 25, 2024
  75. Junio C HamanoSep 24, 2024
  76. Taylor BlauSep 24, 2024
  77. 4/8 pack-objects: use finalize_object_file() to rename pack/idx/etcTaylor Blau, Sep 24, 2024
  78. Junio C HamanoSep 24, 2024
  79. 5/8 sha1: do not redefine `platform_SHA_CTX` and friendsTaylor Blau, Sep 24, 2024
  80. 6/8 hash.h: scaffolding for _unsafe hashing variantsTaylor Blau, Sep 24, 2024
  81. 7/8 Makefile: allow specifying a SHA-1 for non-cryptographic usesTaylor Blau, Sep 24, 2024
  82. 8/8 csum-file.c: use unsafe SHA-1 implementation when availableTaylor Blau, Sep 24, 2024
  83. Jeff KingSep 24, 2024
  84. Elijah NewrenSep 25, 2024
  85. Junio C HamanoSep 25, 2024
  86. Taylor BlauSep 25, 2024
  87. Taylor BlauSep 25, 2024
  88. 0/8 hash.h: support choosing a separate SHA-1 for non-cryptographic usesTaylor Blau, Sep 26, 2024
  89. 1/8 finalize_object_file(): check for name collision before renamingTaylor Blau, Sep 26, 2024
  90. 2/8 finalize_object_file(): refactor unlink_or_warn() placementTaylor Blau, Sep 26, 2024
  91. 3/8 finalize_object_file(): implement collision checkTaylor Blau, Sep 26, 2024
  92. 4/8 pack-objects: use finalize_object_file() to rename pack/idx/etcTaylor Blau, Sep 26, 2024
  93. 5/8 sha1: do not redefine `platform_SHA_CTX` and friendsTaylor Blau, Sep 26, 2024
  94. 6/8 hash.h: scaffolding for _unsafe hashing variantsTaylor Blau, Sep 26, 2024
  95. 7/8 Makefile: allow specifying a SHA-1 for non-cryptographic usesTaylor Blau, Sep 26, 2024
  96. 8/8 csum-file.c: use unsafe SHA-1 implementation when availableTaylor Blau, Sep 26, 2024
  97. Elijah NewrenSep 26, 2024
  98. Junio C HamanoSep 27, 2024
  99. Jeff KingSep 27, 2024

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