# endian_check.cpp

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    00001 /* $Id: endian_check.cpp 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
    00019 #include <stdio.h>
    00020 #include <string.h>
    00021
    00023 enum Endian {
    00024   ENDIAN_LITTLE,
    00025   ENDIAN_BIG
    00026 };
    00027
    00032 static inline void printf_endian(Endian endian)
    00033 {
    00034   printf("#define TTD_ENDIAN %s\n", endian == ENDIAN_LITTLE ? "TTD_LITTLE_ENDIAN" : "TTD_BIG_ENDIAN");
    00035 }
    00036
    00043 int main (int argc, char *argv[])
    00044 {
    00045   unsigned char endian_test[2] = { 1, 0 };
    00046   int force_BE = 0, force_LE = 0, force_PREPROCESSOR = 0;
    00047
    00048   if (argc > 1 && strcmp(argv[1], "BE") == 0) force_BE = 1;
    00049   if (argc > 1 && strcmp(argv[1], "LE") == 0) force_LE = 1;
    00050   if (argc > 1 && strcmp(argv[1], "PREPROCESSOR") == 0) force_PREPROCESSOR = 1;
    00051
    00052   printf("#ifndef ENDIAN_H\n#define ENDIAN_H\n");
    00053
    00054   if (force_LE == 1) {
    00055     printf_endian(ENDIAN_LITTLE);
    00056   } else if (force_BE == 1) {
    00057     printf_endian(ENDIAN_BIG);
    00058   } else if (force_PREPROCESSOR == 1) {
    00059     /* Support for universal binaries on OSX
    00060      * Universal binaries supports both PPC and x86
    00061      * If a compiler for OSX gets this setting, it will always pick the correct endian and no test is needed
    00062      */
    00063     printf("#ifdef __BIG_ENDIAN__\n");
    00064     printf_endian(ENDIAN_BIG);
    00065     printf("#else\n");
    00066     printf_endian(ENDIAN_LITTLE);
    00067     printf("#endif\n");
    00068   } else if (*(short*)endian_test == 1 ) {
    00069     printf_endian(ENDIAN_LITTLE);
    00070   } else {
    00071     printf_endian(ENDIAN_BIG);
    00072   }
    00073   printf("#endif\n");
    00074
    00075   return 0;
    00076 }