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/* Copyright (C) 1992, 1995 Aladdin Enterprises. All rights reserved.
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This software is provided AS-IS with no warranty, either express or
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implied.
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This software is distributed under license and may not be copied,
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modified or distributed except as expressly authorized under the terms
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of the license contained in the file LICENSE in this distribution.
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For more information about licensing, please refer to
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http://www.ghostscript.com/licensing/. For information on
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commercial licensing, go to http://www.artifex.com/licensing/ or
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contact Artifex Software, Inc., 101 Lucas Valley Road #110,
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San Rafael, CA 94903, U.S.A., +1(415)492-9861.
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*/
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/* $Id: shc.c,v 1.4 2002/02/21 22:24:54 giles Exp $ */
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/* Support code for shc.h */
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#include "std.h"
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#include "scommon.h"
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#include "shc.h"
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/* ------ Encoding ------ */
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/* Empty the 1-word buffer onto the output stream. */
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/* q has already been incremented. */
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void
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hc_put_code_proc(bool reverse_bits, byte * q, uint cw)
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{
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#define cb(n) ((byte)(cw >> (n * 8)))
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if (reverse_bits) {
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#if hc_bits_size > 16
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q[-3] = byte_reverse_bits[cb(3)];
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q[-2] = byte_reverse_bits[cb(2)];
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#endif
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q[-1] = byte_reverse_bits[cb(1)];
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q[0] = byte_reverse_bits[cb(0)];
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} else {
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#if hc_bits_size > 16
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q[-3] = cb(3);
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q[-2] = cb(2);
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#endif
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q[-1] = cb(1);
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q[0] = cb(0);
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}
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#undef cb
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}
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/* Put out any final bytes. */
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/* Note that this does a store_state, but not a load_state. */
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byte *
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hc_put_last_bits_proc(stream_hc_state * ss, byte * q, uint bits, int bits_left)
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{
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while (bits_left < hc_bits_size) {
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byte c = (byte) (bits >> (hc_bits_size - 8));
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if (ss->FirstBitLowOrder)
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c = byte_reverse_bits[c];
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*++q = c;
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bits <<= 8;
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bits_left += 8;
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}
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ss->bits = bits;
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ss->bits_left = bits_left;
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return q;
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}
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