1
0
Fork 0
mirror of https://github.com/git/git.git synced 2024-11-05 00:37:55 +01:00
git/ppc/sha1.h
Atousa Pahlevan Duprat 3bc72fde3f sha1: provide another level of indirection for the SHA-1 functions
The git source uses git_SHA1_Update() and friends to call into the
code that computes the hashes.  Traditionally, we used to map these
directly to underlying implementation of the SHA-1 hash (e.g.
SHA1_Update() from OpenSSL or blk_SHA1_Update() from block-sha1/).

This arrangement however makes it hard to tweak behaviour of the
underlying implementation without fully replacing.  If we want to
introduce a tweaked_SHA1_Update() wrapper to implement the "Update"
in a slightly different way, for example, the implementation of the
wrapper still would want to call into the underlying implementation,
but tweaked_SHA1_Update() cannot call git_SHA1_Update() to get to
the underlying implementation (often but not always SHA1_Update()).

Add another level of indirection that maps platform_SHA1_Update()
and friends to their underlying implementations, and by default make
git_SHA1_Update() and friends map to platform_SHA1_* functions.

Doing it this way will later allow us to map git_SHA1_Update() to
tweaked_SHA1_Update(), and the latter can use platform_SHA1_Update()
in its implementation.

Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-11-05 10:35:11 -08:00

25 lines
579 B
C

/*
* SHA-1 implementation.
*
* Copyright (C) 2005 Paul Mackerras <paulus@samba.org>
*/
#include <stdint.h>
typedef struct {
uint32_t hash[5];
uint32_t cnt;
uint64_t len;
union {
unsigned char b[64];
uint64_t l[8];
} buf;
} ppc_SHA_CTX;
int ppc_SHA1_Init(ppc_SHA_CTX *c);
int ppc_SHA1_Update(ppc_SHA_CTX *c, const void *p, unsigned long n);
int ppc_SHA1_Final(unsigned char *hash, ppc_SHA_CTX *c);
#define platform_SHA_CTX ppc_SHA_CTX
#define platform_SHA1_Init ppc_SHA1_Init
#define platform_SHA1_Update ppc_SHA1_Update
#define platform_SHA1_Final ppc_SHA1_Final