/* Digest format and operation */
#define BIN_FORMAT	0x01
#define HEX_FORMAT	0x02
#define IS_XOF		0x08
#define TYPE_MD		0x10
#define TYPE_HMAC	0x20
#define TYPE_CMAC	0x40


/*
 * This structure defines the per-instance state of a digest operation.
 */
typedef struct DigestState {
	Tcl_Channel self;	/* This socket channel */
	Tcl_TimerToken timer;	/* Timer for read events */

	const EVP_CIPHER *cipher, int format, Tcl_Obj *keyObj) {
    char *data;
    int data_len;
    DigestState *statePtr;

    /* Get data */
    data = Tcl_GetByteArrayFromObj(dataObj, &data_len);
    if (data == NULL || data_len == 0) {
	Tcl_SetResult(interp, "No data", NULL);
	return TCL_ERROR;
    }

    /* Create state data structure */
    if ((statePtr = DigestStateNew(interp, format)) == NULL) {
	Tcl_AppendResult(interp, "Memory allocation error", (char *) NULL);

		start++;
	    }
	}
    }

    /* Get options */
    for (idx = start; idx < objc; idx++) {
	char *opt = Tcl_GetStringFromObj(objv[idx], NULL);

	if (opt[0] != '-') {
	    break;
	}

	OPTFLAG("-bin", format, BIN_FORMAT);
	OPTFLAG("-binary", format, BIN_FORMAT);