#pragma once
/**
* Streaming-capable SipHash Implementation
*
* This library provides a SipHash API, that is fully implemented in ISO-C11
* and has no external dependencies. The library performs no memory allocation,
* and provides a streaming API where data to be hashed can be appended
* piecemeal.
*
* A streaming-capable hash state is represented by the "CSipHash" structure,
* which should be initialized with a unique seed before use. If streaming
* capabilities are not required, c_siphash_hash() provides a simple one-shot
* API.
*/
#ifdef __cplusplus
extern "C" {
#endif
#include <stddef.h>
#include <stdint.h>
typedef struct CSipHash CSipHash;
/**
* struct CSipHash - SipHash state object
* @v0-@v3: internal state
* @padding: pending bytes that were not a multiple of 8
* @n_bytes: number of hashed bytes
*
* The state of an inflight hash is represenetd by a CSipHash object. Before
* hashing, it must be initialized with c_siphash_init(), providing a unique
* random hash seed. Data is hashed by appending it to the state object, using
* c_siphash_append(). Finally, the hash is read out by calling
* c_siphash_finalize().
*
* This state object has no allocated resources. It is safe to release its
* backing memory without any further action.
*/
struct CSipHash {
uint64_t v0;
uint64_t v1;
uint64_t v2;
uint64_t v3;
uint64_t padding;
size_t n_bytes;
};
#define C_SIPHASH_NULL {}
void c_siphash_init(CSipHash *state, const uint8_t seed[16]);
void c_siphash_append(CSipHash *state, const uint8_t *bytes, size_t n_bytes);
uint64_t c_siphash_finalize(CSipHash *state);
uint64_t c_siphash_hash(const uint8_t seed[16], const uint8_t *bytes, size_t n_bytes);
#ifdef __cplusplus
}
#endif