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      1 /*
      2  * The copyright in this software is being made available under the 2-clauses
      3  * BSD License, included below. This software may be subject to other third
      4  * party and contributor rights, including patent rights, and no such rights
      5  * are granted under this license.
      6  *
      7  * Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium
      8  * Copyright (c) 2002-2014, Professor Benoit Macq
      9  * Copyright (c) 2003-2007, Francois-Olivier Devaux
     10  * Copyright (c) 2003-2014, Antonin Descampe
     11  * Copyright (c) 2005, Herve Drolon, FreeImage Team
     12  * All rights reserved.
     13  *
     14  * Redistribution and use in source and binary forms, with or without
     15  * modification, are permitted provided that the following conditions
     16  * are met:
     17  * 1. Redistributions of source code must retain the above copyright
     18  *    notice, this list of conditions and the following disclaimer.
     19  * 2. Redistributions in binary form must reproduce the above copyright
     20  *    notice, this list of conditions and the following disclaimer in the
     21  *    documentation and/or other materials provided with the distribution.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
     24  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
     27  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     33  * POSSIBILITY OF SUCH DAMAGE.
     34  */
     35 
     36 #include "opj_includes.h"
     37 
     38 /*
     39 ==========================================================
     40    local functions
     41 ==========================================================
     42 */
     43 
     44 
     45 /*
     46 ==========================================================
     47    RAW encoding interface
     48 ==========================================================
     49 */
     50 
     51 opj_raw_t* opj_raw_create(void) {
     52 	opj_raw_t *raw = (opj_raw_t*)opj_malloc(sizeof(opj_raw_t));
     53 	return raw;
     54 }
     55 
     56 void opj_raw_destroy(opj_raw_t *raw) {
     57 	if(raw) {
     58 		opj_free(raw);
     59 	}
     60 }
     61 
     62 OPJ_UINT32 opj_raw_numbytes(opj_raw_t *raw) {
     63 	const ptrdiff_t diff = raw->bp - raw->start;
     64   assert( diff <= (ptrdiff_t)0xffffffff && diff >= 0 ); /* UINT32_MAX */
     65 	return (OPJ_UINT32)diff;
     66 }
     67 
     68 void opj_raw_init_dec(opj_raw_t *raw, OPJ_BYTE *bp, OPJ_UINT32 len) {
     69 	raw->start = bp;
     70 	raw->lenmax = len;
     71 	raw->len = 0;
     72 	raw->c = 0;
     73 	raw->ct = 0;
     74 }
     75 
     76 OPJ_UINT32 opj_raw_decode(opj_raw_t *raw) {
     77 	OPJ_UINT32 d;
     78 	if (raw->ct == 0) {
     79 		raw->ct = 8;
     80 		if (raw->len == raw->lenmax) {
     81 			raw->c = 0xff;
     82 		} else {
     83 			if (raw->c == 0xff) {
     84 				raw->ct = 7;
     85 			}
     86 			raw->c = *(raw->start + raw->len);
     87 			raw->len++;
     88 		}
     89 	}
     90 	raw->ct--;
     91 	d = (raw->c >> raw->ct) & 0x01;
     92 
     93 	return d;
     94 }
     95 
     96