research.m1stereo.tv/gitweb/ - melted/blob - src/modules/kino/endian_types.h

   1 /* <endian_types.h>
   2  *
   3  * Quick hack to handle endianness and word length issues.
   4  * Defines _le, _be, and _ne variants to standard ISO types
   5  * like int32_t, that are stored in little-endian, big-endian,
   6  * and native-endian byteorder in memory, respectively.
   7  * Caveat: int32_le_t and friends cannot be used in vararg
   8  * functions like printf() without an explicit cast.
   9  *
  10  * Copyright (c) 2003-2005 Daniel Kobras <kobras@debian.org>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software Foundation,
  24  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25  */
  26
  27 #ifndef _ENDIAN_TYPES_H
  28 #define _ENDIAN_TYPES_H
  29
  30 /* Needed for BYTE_ORDER and BIG/LITTLE_ENDIAN macros. */
  31 #ifndef _BSD_SOURCE
  32 # define _BSD_SOURCE
  33 #ifndef __FreeBSD__
  34 # include <endian.h>
  35 #else
  36 # include <sys/endian.h>
  37 #endif /* __FreeBSD__ */
  38 # undef  _BSD_SOURCE
  39 #else
  40 #ifndef __FreeBSD__
  41 # include <endian.h>
  42 #else
  43 # include <sys/endian.h>
  44 #endif /* __FreeBSD__ */
  45 #endif
  46
  47 #include <sys/types.h>
  48 #ifndef __FreeBSD__
  49 #include <byteswap.h>
  50 #else
  51 #define bswap_16(x) bswap16(x)
  52 #define bswap_32(x) bswap32(x)
  53 #define bswap_64(x) bswap64(x)
  54 #endif /* __FreeBSD__ */
  55
  56 static inline int8_t bswap(const int8_t& x)
  57 {
  58         return x;
  59 }
  60
  61 static inline u_int8_t bswap(const u_int8_t& x)
  62 {
  63         return x;
  64 }
  65
  66 static inline int16_t bswap(const int16_t& x)
  67 {
  68         return bswap_16(x);
  69 }
  70
  71 static inline u_int16_t bswap(const u_int16_t& x)
  72 {
  73         return bswap_16(x);
  74 }
  75
  76 static inline int32_t bswap(const int32_t& x)
  77 {
  78         return bswap_32(x);
  79 }
  80
  81 static inline u_int32_t bswap(const u_int32_t& x)
  82 {
  83         return bswap_32(x);
  84 }
  85
  86 static inline int64_t bswap(const int64_t& x)
  87 {
  88         return bswap_64(x);
  89 }
  90
  91 static inline u_int64_t bswap(const u_int64_t& x)
  92 {
  93         return bswap_64(x);
  94 }
  95
  96 #define le_to_cpu       cpu_to_le
  97 #define be_to_cpu       cpu_to_be
  98
  99 template <class T> static inline T cpu_to_le(const T& x)
 100 {
 101 #if BYTE_ORDER == LITTLE_ENDIAN
 102         return x;
 103 #else
 104         return bswap(x);
 105 #endif
 106 }
 107
 108 template <class T> static inline T cpu_to_be(const T& x)
 109 {
 110 #if BYTE_ORDER == LITTLE_ENDIAN
 111         return bswap(x);
 112 #else
 113         return x;
 114 #endif
 115 }
 116
 117 template <class T> class le_t {
 118         T       m;
 119         T       read() const {
 120                 return le_to_cpu(m);
 121         };
 122         void    write(const T& n) {
 123                 m = cpu_to_le(n);
 124         };
 125 public:
 126         le_t(void) {
 127                 m = 0;
 128         };
 129         le_t(const T& o) {
 130                 write(o);
 131         };
 132         operator T() const {
 133                 return read();
 134         };
 135         le_t<T> operator++() {
 136                 write(read() + 1);
 137                 return *this;
 138         };
 139         le_t<T> operator++(int) {
 140                 write(read() + 1);
 141                 return *this;
 142         };
 143         le_t<T> operator--() {
 144                 write(read() - 1);
 145                 return *this;
 146         };
 147         le_t<T> operator--(int) {
 148                 write(read() - 1);
 149                 return *this;
 150         };
 151         le_t<T>& operator+=(const T& t) {
 152                 write(read() + t);
 153                 return *this;
 154         };
 155         le_t<T>& operator-=(const T& t) {
 156                 write(read() - t);
 157                 return *this;
 158         };
 159         le_t<T>& operator&=(const le_t<T>& t) {
 160                 m &= t.m;
 161                 return *this;
 162         };
 163         le_t<T>& operator|=(const le_t<T>& t) {
 164                 m |= t.m;
 165                 return *this;
 166         };
 167 } __attribute__((packed));
 168
 169 /* Just copy-and-pasted from le_t. Too lazy to do it right. */
 170
 171 template <class T> class be_t {
 172         T       m;
 173         T       read() const {
 174                 return be_to_cpu(m);
 175         };
 176         void    write(const T& n) {
 177                 m = cpu_to_be(n);
 178         };
 179 public:
 180         be_t(void) {
 181                 m = 0;
 182         };
 183         be_t(const T& o) {
 184                 write(o);
 185         };
 186         operator T() const {
 187                 return read();
 188         };
 189         be_t<T> operator++() {
 190                 write(read() + 1);
 191                 return *this;
 192         };
 193         be_t<T> operator++(int) {
 194                 write(read() + 1);
 195                 return *this;
 196         };
 197         be_t<T> operator--() {
 198                 write(read() - 1);
 199                 return *this;
 200         };
 201         be_t<T> operator--(int) {
 202                 write(read() - 1);
 203                 return *this;
 204         };
 205         be_t<T>& operator+=(const T& t) {
 206                 write(read() + t);
 207                 return *this;
 208         };
 209         be_t<T>& operator-=(const T& t) {
 210                 write(read() - t);
 211                 return *this;
 212         };
 213         be_t<T>& operator&=(const be_t<T>& t) {
 214                 m &= t.m;
 215                 return *this;
 216         };
 217         be_t<T>& operator|=(const be_t<T>& t) {
 218                 m |= t.m;
 219                 return *this;
 220         };
 221 } __attribute__((packed));
 222
 223 /* Define types of native endianness similar to the little and big endian
 224  * versions below. Not really necessary but useful occasionally to emphasize
 225  * endianness of data.
 226  */
 227
 228 typedef int8_t          int8_ne_t;
 229 typedef int16_t         int16_ne_t;
 230 typedef int32_t         int32_ne_t;
 231 typedef int64_t         int64_ne_t;
 232 typedef u_int8_t        u_int8_ne_t;
 233 typedef u_int16_t       u_int16_ne_t;
 234 typedef u_int32_t       u_int32_ne_t;
 235 typedef u_int64_t       u_int64_ne_t;
 236
 237
 238 /* The classes work on their native endianness as well, but obviously
 239  * introduce some overhead.  Use the faster typedefs to native types
 240  * therefore, unless you're debugging.
 241  */
 242
 243 #if BYTE_ORDER == LITTLE_ENDIAN
 244 typedef int8_ne_t       int8_le_t;
 245 typedef int16_ne_t      int16_le_t;
 246 typedef int32_ne_t      int32_le_t;
 247 typedef int64_ne_t      int64_le_t;
 248 typedef u_int8_ne_t     u_int8_le_t;
 249 typedef u_int16_ne_t    u_int16_le_t;
 250 typedef u_int32_ne_t    u_int32_le_t;
 251 typedef u_int64_ne_t    u_int64_le_t;
 252 typedef int8_t          int8_be_t;
 253 typedef be_t<int16_t>   int16_be_t;
 254 typedef be_t<int32_t>   int32_be_t;
 255 typedef be_t<int64_t>   int64_be_t;
 256 typedef u_int8_t        u_int8_be_t;
 257 typedef be_t<u_int16_t> u_int16_be_t;
 258 typedef be_t<u_int32_t> u_int32_be_t;
 259 typedef be_t<u_int64_t> u_int64_be_t;
 260 #else
 261 typedef int8_ne_t       int8_be_t;
 262 typedef int16_ne_t      int16_be_t;
 263 typedef int32_ne_t      int32_be_t;
 264 typedef int64_ne_t      int64_be_t;
 265 typedef u_int8_ne_t     u_int8_be_t;
 266 typedef u_int16_ne_t    u_int16_be_t;
 267 typedef u_int32_ne_t    u_int32_be_t;
 268 typedef u_int64_ne_t    u_int64_be_t;
 269 typedef int8_t          int8_le_t;
 270 typedef le_t<int16_t>   int16_le_t;
 271 typedef le_t<int32_t>   int32_le_t;
 272 typedef le_t<int64_t>   int64_le_t;
 273 typedef u_int8_t        u_int8_le_t;
 274 typedef le_t<u_int16_t> u_int16_le_t;
 275 typedef le_t<u_int32_t> u_int32_le_t;
 276 typedef le_t<u_int64_t> u_int64_le_t;
 277 #endif
 278
 279 #endif