h.sum = nil
}

func (h *boringHMAC) finalize() {
	C._goboringcrypto_HMAC_CTX_cleanup(&h.ctx)
}

func (h *boringHMAC) Write(p []byte) (int, error) {
	if len(p) > 0 {
		C._goboringcrypto_HMAC_Update(&h.ctx, (*C.uint8_t)(unsafe.Pointer(&p[0])), C.size_t(len(p)))
	}
	runtime.KeepAlive(h)
	return len(p), nil
}

func (h *boringHMAC) Size() int {
	return h.size
}

void _goboringcrypto_HMAC_CTX_init(GO_HMAC_CTX*);
void _goboringcrypto_HMAC_CTX_cleanup(GO_HMAC_CTX*);
int _goboringcrypto_HMAC_Init(GO_HMAC_CTX*, const void*, int, const GO_EVP_MD*);
int _goboringcrypto_HMAC_Update(GO_HMAC_CTX*, const uint8_t*, size_t);
int _goboringcrypto_HMAC_Final(GO_HMAC_CTX*, uint8_t*, unsigned int*);
size_t _goboringcrypto_HMAC_size(const GO_HMAC_CTX*);