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#ifndef HASH_H
#define HASH_H
#include "git-compat-util.h"
#if defined(SHA1_PPC)
#include "ppc/sha1.h"
#elif defined(SHA1_APPLE)
#include <CommonCrypto/CommonDigest.h>
#elif defined(SHA1_OPENSSL)
#include <openssl/sha.h>
#elif defined(SHA1_DC)
#include "sha1dc_git.h"
#else /* SHA1_BLK */
#include "block-sha1/sha1.h"
#endif
#ifndef platform_SHA_CTX
/*
* platform's underlying implementation of SHA-1; could be OpenSSL,
* blk_SHA, Apple CommonCrypto, etc... Note that the relevant
* SHA-1 header may have already defined platform_SHA_CTX for our
* own implementations like block-sha1 and ppc-sha1, so we list
* the default for OpenSSL compatible SHA-1 implementations here.
*/
#define platform_SHA_CTX SHA_CTX
#define platform_SHA1_Init SHA1_Init
#define platform_SHA1_Update SHA1_Update
#define platform_SHA1_Final SHA1_Final
#endif
#define git_SHA_CTX platform_SHA_CTX
#define git_SHA1_Init platform_SHA1_Init
#define git_SHA1_Update platform_SHA1_Update
#define git_SHA1_Final platform_SHA1_Final
#ifdef SHA1_MAX_BLOCK_SIZE
#include "compat/sha1-chunked.h"
#undef git_SHA1_Update
#define git_SHA1_Update git_SHA1_Update_Chunked
#endif
/*
* Note that these constants are suitable for indexing the hash_algos array and
* comparing against each other, but are otherwise arbitrary, so they should not
* be exposed to the user or serialized to disk. To know whether a
* git_hash_algo struct points to some usable hash function, test the format_id
* field for being non-zero. Use the name field for user-visible situations and
* the format_id field for fixed-length fields on disk.
*/
/* An unknown hash function. */
#define GIT_HASH_UNKNOWN 0
/* SHA-1 */
#define GIT_HASH_SHA1 1
/* Number of algorithms supported (including unknown). */
#define GIT_HASH_NALGOS (GIT_HASH_SHA1 + 1)
/* A suitably aligned type for stack allocations of hash contexts. */
union git_hash_ctx {
git_SHA_CTX sha1;
};
typedef union git_hash_ctx git_hash_ctx;
typedef void (*git_hash_init_fn)(git_hash_ctx *ctx);
typedef void (*git_hash_update_fn)(git_hash_ctx *ctx, const void *in, size_t len);
typedef void (*git_hash_final_fn)(unsigned char *hash, git_hash_ctx *ctx);
struct git_hash_algo {
/*
* The name of the algorithm, as appears in the config file and in
* messages.
*/
const char *name;
/* A four-byte version identifier, used in pack indices. */
uint32_t format_id;
/* The length of the hash in binary. */
size_t rawsz;
/* The length of the hash in hex characters. */
size_t hexsz;
/* The hash initialization function. */
git_hash_init_fn init_fn;
/* The hash update function. */
git_hash_update_fn update_fn;
/* The hash finalization function. */
git_hash_final_fn final_fn;
/* The OID of the empty tree. */
const struct object_id *empty_tree;
/* The OID of the empty blob. */
const struct object_id *empty_blob;
};
extern const struct git_hash_algo hash_algos[GIT_HASH_NALGOS];
#endif