mirror of
https://github.com/KolibriOS/kolibrios.git
synced 2024-12-24 15:46:49 +03:00
46 lines
1.3 KiB
C
46 lines
1.3 KiB
C
/*
|
|
getbits
|
|
|
|
copyright ?-2006 by the mpg123 project - free software under the terms of the LGPL 2.1
|
|
see COPYING and AUTHORS files in distribution or http://mpg123.de
|
|
initially written by Michael Hipp
|
|
*/
|
|
|
|
#ifndef _MPG123_GETBITS_H_
|
|
#define _MPG123_GETBITS_H_
|
|
|
|
/* that's the same file as getits.c but with defines to
|
|
force inlining */
|
|
|
|
static unsigned long rval;
|
|
static unsigned char rval_uc;
|
|
|
|
#define backbits(nob) ((void)( \
|
|
bsi.bitindex -= nob, \
|
|
bsi.wordpointer += (bsi.bitindex>>3), \
|
|
bsi.bitindex &= 0x7 ))
|
|
|
|
#define getbitoffset() ((-bsi.bitindex)&0x7)
|
|
#define getbyte() (*bsi.wordpointer++)
|
|
|
|
#define getbits(nob) ( \
|
|
rval = bsi.wordpointer[0], rval <<= 8, rval |= bsi.wordpointer[1], \
|
|
rval <<= 8, rval |= bsi.wordpointer[2], rval <<= bsi.bitindex, \
|
|
rval &= 0xffffff, bsi.bitindex += nob, \
|
|
rval >>= (24-nob), bsi.wordpointer += (bsi.bitindex>>3), \
|
|
bsi.bitindex &= 7,rval)
|
|
|
|
#define getbits_fast(nob) ( \
|
|
rval = (unsigned char) (bsi.wordpointer[0] << bsi.bitindex), \
|
|
rval |= ((unsigned long) bsi.wordpointer[1]<<bsi.bitindex)>>8, \
|
|
rval <<= nob, rval >>= 8, \
|
|
bsi.bitindex += nob, bsi.wordpointer += (bsi.bitindex>>3), \
|
|
bsi.bitindex &= 7, rval )
|
|
|
|
#define get1bit() ( \
|
|
rval_uc = *bsi.wordpointer << bsi.bitindex, bsi.bitindex++, \
|
|
bsi.wordpointer += (bsi.bitindex>>3), bsi.bitindex &= 7, rval_uc>>7 )
|
|
|
|
|
|
#endif
|