/* Copyright (C) 2001-2021 Artifex Software, Inc.

   All Rights Reserved.

   This software is provided AS-IS with no warranty, either express or

   implied.

   This software is distributed under license and may not be copied,

   modified or distributed except as expressly authorized under the terms

   of the license contained in the file LICENSE in this distribution.

   Refer to licensing information at http://www.artifex.com or contact

   Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,

   CA 94945, U.S.A., +1(415)492-9861, for further information.

*/

/* Support code for shc.h */

#include "std.h"

#include "scommon.h"

#include "shc.h"

/* ------ Encoding ------ */

/* Empty the 1-word buffer onto the output stream. */

/* q has already been incremented. */

void

hc_put_code_proc(bool reverse_bits, byte * q, uint cw)

{

#define cb(n) ((byte)(cw >> (n * 8)))

    if (reverse_bits) {

#if hc_bits_size > 16

        q[-3] = byte_reverse_bits[cb(3)];

        q[-2] = byte_reverse_bits[cb(2)];

#endif

        q[-1] = byte_reverse_bits[cb(1)];

        q[0] = byte_reverse_bits[cb(0)];

    } else {

#if hc_bits_size > 16

        q[-3] = cb(3);

        q[-2] = cb(2);

#endif

        q[-1] = cb(1);

        q[0] = cb(0);

    }

#undef cb

}

/* Put out any final bytes. */

/* Note that this does a store_state, but not a load_state. */

byte *

hc_put_last_bits_proc(stream_hc_state * ss, byte * q, uint bits, int bits_left)

{

    while (bits_left < hc_bits_size) {

        byte c = (byte) (bits >> (hc_bits_size - 8));

        if (ss->FirstBitLowOrder)

            c = byte_reverse_bits[c];

        *++q = c;

        bits <<= 8;

        bits_left += 8;

    }

    ss->bits = bits;

    ss->bits_left = bits_left;

    return q;

}