# endian_func.hpp

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    00001 /* $Id: endian_func.hpp 17248 2009-08-21 20:21:05Z rubidium $ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD 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, version 2.
    00006  * OpenTTD 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.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #ifndef ENDIAN_FUNC_HPP
    00013 #define ENDIAN_FUNC_HPP
    00014
    00015 #include "endian_type.hpp"
    00016 #include "bitmath_func.hpp"
    00017
    00018 /* Setup alignment and conversion macros */
    00019 #if TTD_ENDIAN == TTD_BIG_ENDIAN
    00020   #define FROM_BE16(x) (x)
    00021   #define FROM_BE32(x) (x)
    00022   #define TO_BE16(x)   (x)
    00023   #define TO_BE32(x)   (x)
    00024   #define TO_BE32X(x)  (x)
    00025   #define FROM_LE16(x) BSWAP16(x)
    00026   #define FROM_LE32(x) BSWAP32(x)
    00027   #define TO_LE16(x)   BSWAP16(x)
    00028   #define TO_LE32(x)   BSWAP32(x)
    00029   #define TO_LE32X(x)  BSWAP32(x)
    00030 #else
    00031   #define FROM_BE16(x) BSWAP16(x)
    00032   #define FROM_BE32(x) BSWAP32(x)
    00033   #define TO_BE16(x)   BSWAP16(x)
    00034   #define TO_BE32(x)   BSWAP32(x)
    00035   #define TO_BE32X(x)  BSWAP32(x)
    00036   #define FROM_LE16(x) (x)
    00037   #define FROM_LE32(x) (x)
    00038   #define TO_LE16(x)   (x)
    00039   #define TO_LE32(x)   (x)
    00040   #define TO_LE32X(x)  (x)
    00041 #endif /* TTD_ENDIAN == TTD_BIG_ENDIAN */
    00042
    00043 static FORCEINLINE uint16 ReadLE16Aligned(const void *x)
    00044 {
    00045   return FROM_LE16(*(const uint16*)x);
    00046 }
    00047
    00048 static FORCEINLINE uint16 ReadLE16Unaligned(const void *x)
    00049 {
    00050 #if OTTD_ALIGNMENT == 1
    00051   return ((const byte*)x)[0] | ((const byte*)x)[1] << 8;
    00052 #else
    00053   return FROM_LE16(*(const uint16*)x);
    00054 #endif /* OTTD_ALIGNMENT == 1 */
    00055 }
    00056
    00057 #endif /* ENDIAN_FUNC_HPP */