/*** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com**** This program 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 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 General Public License for more details.**** You should have received a copy of the GNU General Public License** along with this program; if not, write to the Free Software** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.**** Any non-GPL usage of this software or parts of this software is strictly** forbidden.**** The "appropriate copyright message" mentioned in section 2c of the GPLv2** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"**** Commercial non-GPL licensing of this software is possible.** For more info contact Nero AG through Mpeg4AAClicense@nero.com.**** $Id: bits.h,v 1.45 2007/11/01 12:33:29 menno Exp $**/ #ifndef __BITS_H__#define __BITS_H__ #ifdef __cplusplusextern "C" {#endif #include "analysis.h"#ifdef ANALYSIS#include <stdio.h>#endif #define BYTE_NUMBIT     8#define BYTE_NUMBIT_LD  3//#define bit2byte(a) ((a+7)/BYTE_NUMBIT)#define bit2byte(a) ((a+7)>>BYTE_NUMBIT_LD) typedef struct _bitfile{    const void *buffer;    uint32_t *tail;    uint32_t *start;    /* bit input */    uint32_t bufa;    uint32_t bufb;    uint32_t bits_left;    uint32_t buffer_size; /* size of the buffer in bytes */    uint32_t bytes_left;    uint8_t error;} bitfile;  #if 0static uint32_t const bitmask[] = {    0x0, 0x1, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF,    0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF,    0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF,    0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF, 0x7FFFFFF,    0xFFFFFFF, 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF    /* added bitmask 32, correct?!?!?! */    , 0xFFFFFFFF};#endif void faad_initbits(bitfile *ld, const void *buffer, const uint32_t buffer_size);void faad_endbits(bitfile *ld);#if 0void faad_initbits_rev(bitfile *ld, void *buffer,                       uint32_t bits_in_buffer);#endifuint8_t faad_byte_align(bitfile *ld);uint32_t faad_get_processed_bits(bitfile *ld);void faad_flushbits_ex(bitfile *ld, uint32_t bits);#ifdef DRMvoid faad_rewindbits(bitfile *ld);#endifvoid faad_resetbits(bitfile *ld, uint32_t bits);uint8_t *faad_getbitbuffer(bitfile *ld, uint32_t bits                       DEBUGDEC);#ifdef DRMvoid *faad_origbitbuffer(bitfile *ld);uint32_t faad_origbitbuffer_size(bitfile *ld);#endif /* circumvent memory alignment errors on ARM */static INLINE uint32_t getdword(void *mem){    uint8_t* m8 = (uint8_t*)mem;    return (uint32_t)m8[3] | ((uint32_t)m8[2] << 8) | ((uint32_t)m8[1] << 16) | ((uint32_t)m8[0] << 24);} static INLINE uint32_t faad_showbits(bitfile *ld, uint32_t bits){    if (bits <= ld->bits_left)    {        //return (ld->bufa >> (ld->bits_left - bits)) & bitmask[bits];        return (ld->bufa << (32 - ld->bits_left)) >> (32 - bits);    }     bits -= ld->bits_left;    //return ((ld->bufa & bitmask[ld->bits_left]) << bits) | (ld->bufb >> (32 - bits));    return ((ld->bufa & ((1u<<ld->bits_left)-1)) << bits) | (ld->bufb >> (32 - bits));} static INLINE void faad_flushbits(bitfile *ld, uint32_t bits){    /* do nothing if error */    if (ld->error != 0)        return;     if (bits < ld->bits_left)    {        ld->bits_left -= bits;    } else {        faad_flushbits_ex(ld, bits);    }} /* return next n bits (right adjusted) */static /*INLINE*/ uint32_t faad_getbits(bitfile *ld, uint32_t n DEBUGDEC){    uint32_t ret;     if (n == 0)        return 0;     ret = faad_showbits(ld, n);    faad_flushbits(ld, n); #ifdef ANALYSIS    if (print)        fprintf(stdout, "%4d %2d bits, val: %4d, variable: %d %s\n", dbg_count++, n, ret, var, dbg);#endif     return ret;} static INLINE uint8_t faad_get1bit(bitfile *ld DEBUGDEC){    uint8_t r;     if (ld->bits_left > 0)    {        ld->bits_left--;        r = (uint8_t)((ld->bufa >> ld->bits_left) & 1);        return r;    }     /* bits_left == 0 */#if 0    r = (uint8_t)(ld->bufb >> 31);    faad_flushbits_ex(ld, 1);#else    r = (uint8_t)faad_getbits(ld, 1);#endif    return r;} #if 0/* reversed bitreading routines */static INLINE uint32_t faad_showbits_rev(bitfile *ld, uint32_t bits){    uint8_t i;    uint32_t B = 0;     if (bits <= ld->bits_left)    {        for (i = 0; i < bits; i++)        {            if (ld->bufa & (1u << (i + (32 - ld->bits_left))))                B |= (1u << (bits - i - 1));        }        return B;    } else {        for (i = 0; i < ld->bits_left; i++)        {            if (ld->bufa & (1u << (i + (32 - ld->bits_left))))                B |= (1u << (bits - i - 1));        }        for (i = 0; i < bits - ld->bits_left; i++)        {            if (ld->bufb & (1u << (i + (32-ld->bits_left))))                B |= (1u << (bits - ld->bits_left - i - 1));        }        return B;    }} static INLINE void faad_flushbits_rev(bitfile *ld, uint32_t bits){    /* do nothing if error */    if (ld->error != 0)        return;     if (bits < ld->bits_left)    {        ld->bits_left -= bits;    } else {        uint32_t tmp;         ld->bufa = ld->bufb;        tmp = getdword(ld->start);        ld->bufb = tmp;        ld->start--;        ld->bits_left += (32 - bits);         if (ld->bytes_left < 4)        {            ld->error = 1;            ld->bytes_left = 0;        } else {            ld->bytes_left -= 4;        }//        if (ld->bytes_left == 0)//            ld->no_more_reading = 1;    }} static /*INLINE*/ uint32_t faad_getbits_rev(bitfile *ld, uint32_t n                                        DEBUGDEC){    uint32_t ret;     if (n == 0)        return 0;     ret = faad_showbits_rev(ld, n);    faad_flushbits_rev(ld, n); #ifdef ANALYSIS    if (print)        fprintf(stdout, "%4d %2d bits, val: %4d, variable: %d %s\n", dbg_count++, n, ret, var, dbg);#endif     return ret;}#endif #ifdef DRM/* CRC lookup table for G8 polynome in DRM standard */static const uint8_t crc_table_G8[256] = {    0x0, 0x1d, 0x3a, 0x27, 0x74, 0x69, 0x4e, 0x53,    0xe8, 0xf5, 0xd2, 0xcf, 0x9c, 0x81, 0xa6, 0xbb,    0xcd, 0xd0, 0xf7, 0xea, 0xb9, 0xa4, 0x83, 0x9e,    0x25, 0x38, 0x1f, 0x2, 0x51, 0x4c, 0x6b, 0x76,    0x87, 0x9a, 0xbd, 0xa0, 0xf3, 0xee, 0xc9, 0xd4,    0x6f, 0x72, 0x55, 0x48, 0x1b, 0x6, 0x21, 0x3c,    0x4a, 0x57, 0x70, 0x6d, 0x3e, 0x23, 0x4, 0x19,    0xa2, 0xbf, 0x98, 0x85, 0xd6, 0xcb, 0xec, 0xf1,    0x13, 0xe, 0x29, 0x34, 0x67, 0x7a, 0x5d, 0x40,    0xfb, 0xe6, 0xc1, 0xdc, 0x8f, 0x92, 0xb5, 0xa8,    0xde, 0xc3, 0xe4, 0xf9, 0xaa, 0xb7, 0x90, 0x8d,    0x36, 0x2b, 0xc, 0x11, 0x42, 0x5f, 0x78, 0x65,    0x94, 0x89, 0xae, 0xb3, 0xe0, 0xfd, 0xda, 0xc7,    0x7c, 0x61, 0x46, 0x5b, 0x8, 0x15, 0x32, 0x2f,    0x59, 0x44, 0x63, 0x7e, 0x2d, 0x30, 0x17, 0xa,    0xb1, 0xac, 0x8b, 0x96, 0xc5, 0xd8, 0xff, 0xe2,    0x26, 0x3b, 0x1c, 0x1, 0x52, 0x4f, 0x68, 0x75,    0xce, 0xd3, 0xf4, 0xe9, 0xba, 0xa7, 0x80, 0x9d,    0xeb, 0xf6, 0xd1, 0xcc, 0x9f, 0x82, 0xa5, 0xb8,    0x3, 0x1e, 0x39, 0x24, 0x77, 0x6a, 0x4d, 0x50,    0xa1, 0xbc, 0x9b, 0x86, 0xd5, 0xc8, 0xef, 0xf2,    0x49, 0x54, 0x73, 0x6e, 0x3d, 0x20, 0x7, 0x1a,    0x6c, 0x71, 0x56, 0x4b, 0x18, 0x5, 0x22, 0x3f,    0x84, 0x99, 0xbe, 0xa3, 0xf0, 0xed, 0xca, 0xd7,    0x35, 0x28, 0xf, 0x12, 0x41, 0x5c, 0x7b, 0x66,    0xdd, 0xc0, 0xe7, 0xfa, 0xa9, 0xb4, 0x93, 0x8e,    0xf8, 0xe5, 0xc2, 0xdf, 0x8c, 0x91, 0xb6, 0xab,    0x10, 0xd, 0x2a, 0x37, 0x64, 0x79, 0x5e, 0x43,    0xb2, 0xaf, 0x88, 0x95, 0xc6, 0xdb, 0xfc, 0xe1,    0x5a, 0x47, 0x60, 0x7d, 0x2e, 0x33, 0x14, 0x9,    0x7f, 0x62, 0x45, 0x58, 0xb, 0x16, 0x31, 0x2c,    0x97, 0x8a, 0xad, 0xb0, 0xe3, 0xfe, 0xd9, 0xc4,}; static INLINE uint8_t faad_check_CRC(bitfile *ld, uint16_t len){    int bytes, rem;    unsigned int CRC;    unsigned int r=255;  /* Initialize to all ones */     /* CRC polynome used x^8 + x^4 + x^3 + x^2 +1 */#define GPOLY 0435     faad_rewindbits(ld);     CRC = (unsigned int) ~faad_getbits(ld, 8        DEBUGVAR(1,999,"faad_check_CRC(): CRC")) & 0xFF;          /* CRC is stored inverted */     bytes = len >> 3;    rem = len & 0x7;     for (; bytes > 0; bytes--)    {        r = crc_table_G8[( r ^ faad_getbits(ld, 8 DEBUGVAR(1,998,"")) ) & 0xFF];    }    for (; rem > 0; rem--)    {        r = ( (r << 1) ^ (( ( faad_get1bit(ld            DEBUGVAR(1,998,""))  & 1) ^ ((r >> 7) & 1)) * GPOLY )) & 0xFF;    }     if (r != CRC)  //  if (0)    {        return 28;    } else {        return 0;    }} #ifdef SBR_DECstatic uint8_t tabFlipbits[256] = {    0,128,64,192,32,160,96,224,16,144,80,208,48,176,112,240,    8,136,72,200,40,168,104,232,24,152,88,216,56,184,120,248,    4,132,68,196,36,164,100,228,20,148,84,212,52,180,116,244,    12,140,76,204,44,172,108,236,28,156,92,220,60,188,124,252,    2,130,66,194,34,162,98,226,18,146,82,210,50,178,114,242,    10,138,74,202,42,170,106,234,26,154,90,218,58,186,122,250,    6,134,70,198,38,166,102,230,22,150,86,214,54,182,118,246,    14,142,78,206,46,174,110,238,30,158,94,222,62,190,126,254,    1,129,65,193,33,161,97,225,17,145,81,209,49,177,113,241,    9,137,73,201,41,169,105,233,25,153,89,217,57,185,121,249,    5,133,69,197,37,165,101,229,21,149,85,213,53,181,117,245,    13,141,77,205,45,173,109,237,29,157,93,221,61,189,125,253,    3,131,67,195,35,163,99,227,19,147,83,211,51,179,115,243,    11,139,75,203,43,171,107,235,27,155,91,219,59,187,123,251,    7,135,71,199,39,167,103,231,23,151,87,215,55,183,119,247,    15,143,79,207,47,175,111,239,31,159,95,223,63,191,127,255};static INLINE uint8_t reverse_byte(uint8_t b){    return tabFlipbits[b];}#endif#endif #ifdef ERROR_RESILIENCE /* Modified bit reading functions for HCR */ typedef struct{    /* bit input */    uint32_t bufa;    uint32_t bufb;    int8_t len;} bits_t; /* PRECONDITION: bits <= 32 */static INLINE uint32_t showbits_hcr(bits_t *ld, uint8_t bits){    uint32_t mask;    int8_t tail;    if (bits == 0) return 0;    if (ld->len == 0) return 0;    tail = ld->len - bits;    mask = 0xFFFFFFFF >> (32 - bits);    if (ld->len <= 32)    {        /* huffman_spectral_data_2 might request more than available (tail < 0),           pad with zeroes then. */        if (tail >= 0)            return (ld->bufa >> tail) & mask; /* tail is 0..31 */        else            return (ld->bufa << -tail) & mask; /* -tail is 1..31 */    } else {        /* tail is 1..63 */        if (tail < 32)            return ((ld->bufb << (32 - tail)) | (ld->bufa >> tail)) & mask;        else            return (ld->bufb >> (tail - 32)) & mask;    }} /* return 1 if position is outside of buffer, 0 otherwise */static INLINE int8_t flushbits_hcr( bits_t *ld, uint8_t bits){    ld->len -= bits;     if (ld->len <0)    {        ld->len = 0;        return 1;    } else {        return 0;    }} static INLINE int8_t getbits_hcr(bits_t *ld, uint8_t n, uint32_t *result){    *result = showbits_hcr(ld, n);    return flushbits_hcr(ld, n);} static INLINE int8_t get1bit_hcr(bits_t *ld, uint8_t *result){    uint32_t res;    int8_t ret;     ret = getbits_hcr(ld, 1, &res);    *result = (int8_t)(res & 1);    return ret;} #endif  #ifdef __cplusplus}#endif#endif