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- /*
- * bitstream.h
- *
- * Copyright (C) Aaron Holtzman - Dec 1999
- *
- * This file is part of ac3dec, a free AC-3 audio decoder
- *
- * ac3dec is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * ac3dec 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU Make; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
-
- //My new and improved vego-matic endian swapping routine
- //(stolen from the kernel)
- #ifdef WORDS_BIGENDIAN
-
- # define swab32(x) (x)
-
- #else
-
- # if defined (__i386__)
-
- # define swab32(x) __i386_swab32(x)
- static inline const uint_32 __i386_swab32(uint_32 x)
- {
- __asm__("bswap %0" : "=r" (x) : "0" (x));
- return x;
- }
-
- # else
-
- # define swab32(x)\
- ((((uint_8*)&x)[0] << 24) | (((uint_8*)&x)[1] << 16) | \
- (((uint_8*)&x)[2] << 8) | (((uint_8*)&x)[3]))
-
- # endif
- #endif
-
- extern uint_32 bits_left;
- extern uint_32 current_word;
-
- void bitstream_init(void(*fill_function)(uint_8**,uint_8**));
-
- uint_8 bitstream_get_byte(void);
-
- uint_8 *bitstream_get_buffer_start(void);
- void bitstream_buffer_frame(uint_32 frame_size);
-
- uint_32 bitstream_get_bh(uint_32 num_bits);
-
- static inline uint_32
- bitstream_get(uint_32 num_bits)
- {
- uint_32 result;
-
- if(num_bits < bits_left)
- {
- result = (current_word << (32 - bits_left)) >> (32 - num_bits);
- bits_left -= num_bits;
- return result;
- }
-
- return bitstream_get_bh(num_bits);
- }
-
-