Function openssl_sys::EVP_DigestSignInit

pub unsafe extern fn EVP_DigestSignInit(ctx: *mut EVP_MD_CTX,
                                        pctx: *mut *mut EVP_PKEY_CTX,
                                        type_: *const EVP_MD,
                                        e: *mut ENGINE,
                                        pkey: *mut EVP_PKEY)
                                        -> c_int