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/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* leb128 handling implementations
*/
#ifndef AVCODEC_LEB_H
#define AVCODEC_LEB_H
#include "get_bits.h"
/**
* Read a unsigned integer coded as a variable number of up to eight
* little-endian bytes, where the MSB in a byte signals another byte
* must be read.
* All coded bits are read, but values > UINT_MAX are truncated.
*/
static inline unsigned get_leb(GetBitContext *s) {
int more, i = 0;
unsigned leb = 0;
do {
int byte = get_bits(s, 8);
unsigned bits = byte & 0x7f;
more = byte & 0x80;
if (i <= 4)
leb |= bits << (i * 7);
if (++i == 8)
break;
} while (more);
return leb;
}
/**
* Read a unsigned integer coded as a variable number of up to eight
* little-endian bytes, where the MSB in a byte signals another byte
* must be read.
*/
static inline int64_t get_leb128(GetBitContext *gb) {
int64_t ret = 0;
for (int i = 0; i < 8; i++) {
int byte = get_bits(gb, 8);
ret |= (int64_t)(byte & 0x7f) << (i * 7);
if (!(byte & 0x80))
break;
}
return ret;
}
#endif /* AVCODEC_LEB_H */
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