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mirror of https://code.videolan.org/videolan/vlc synced 2024-09-12 13:44:56 +02:00
vlc/modules/mux/mpeg/bits.h
2019-01-17 12:21:18 +01:00

85 lines
2.4 KiB
C

/*****************************************************************************
* bits.h
*****************************************************************************
* Copyright (C) 2001, 2002 VLC authors and VideoLAN
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
* Eric Petit <titer@videolan.org>
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
typedef struct bits_buffer_s
{
int i_size;
int i_data;
uint8_t i_mask;
uint8_t *p_data;
} bits_buffer_t;
static inline int bits_initwrite( bits_buffer_t *p_buffer,
int i_size, void *p_data )
{
p_buffer->i_size = i_size;
p_buffer->i_data = 0;
p_buffer->i_mask = 0x80;
p_buffer->p_data = p_data;
if( !p_buffer->p_data )
{
if( !( p_buffer->p_data = malloc( i_size ) ) )
return -1;
}
p_buffer->p_data[0] = 0;
return 0;
}
static inline void bits_align( bits_buffer_t *p_buffer )
{
if( p_buffer->i_mask != 0x80 && p_buffer->i_data < p_buffer->i_size )
{
p_buffer->i_mask = 0x80;
p_buffer->i_data++;
p_buffer->p_data[p_buffer->i_data] = 0x00;
}
}
static inline void bits_write( bits_buffer_t *p_buffer,
int i_count, uint64_t i_bits )
{
while( i_count > 0 )
{
i_count--;
if( ( i_bits >> i_count )&0x01 )
{
p_buffer->p_data[p_buffer->i_data] |= p_buffer->i_mask;
}
else
{
p_buffer->p_data[p_buffer->i_data] &= ~p_buffer->i_mask;
}
p_buffer->i_mask >>= 1;
if( p_buffer->i_mask == 0 )
{
p_buffer->i_data++;
p_buffer->i_mask = 0x80;
}
}
}