# endian_check.cpp

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    00001 /* $Id$ */
    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
    00021 #include <stdio.h>
    00022 #include <string.h>
    00023
    00025 enum Endian {
    00026   ENDIAN_LITTLE,
    00027   ENDIAN_BIG,
    00028 };
    00029
    00034 static inline void printf_endian(Endian endian)
    00035 {
    00036   printf("#define TTD_ENDIAN %s\n", endian == ENDIAN_LITTLE ? "TTD_LITTLE_ENDIAN" : "TTD_BIG_ENDIAN");
    00037 }
    00038
    00045 int main (int argc, char *argv[])
    00046 {
    00047   unsigned char endian_test[2] = { 1, 0 };
    00048   int force_BE = 0, force_LE = 0, force_PREPROCESSOR = 0;
    00049
    00050   if (argc > 1 && strcmp(argv[1], "BE") == 0) force_BE = 1;
    00051   if (argc > 1 && strcmp(argv[1], "LE") == 0) force_LE = 1;
    00052   if (argc > 1 && strcmp(argv[1], "PREPROCESSOR") == 0) force_PREPROCESSOR = 1;
    00053
    00054   printf("#ifndef ENDIAN_H\n#define ENDIAN_H\n");
    00055
    00056   if (force_LE == 1) {
    00057     printf_endian(ENDIAN_LITTLE);
    00058   } else if (force_BE == 1) {
    00059     printf_endian(ENDIAN_BIG);
    00060   } else if (force_PREPROCESSOR == 1) {
    00061     /* Support for universal binaries on OSX
    00062      * Universal binaries supports both PPC and x86
    00063      * If a compiler for OSX gets this setting, it will always pick the correct endian and no test is needed
    00064      */
    00065     printf("#ifdef __BIG_ENDIAN__\n");
    00066     printf_endian(ENDIAN_BIG);
    00067     printf("#else\n");
    00068     printf_endian(ENDIAN_LITTLE);
    00069     printf("#endif\n");
    00070   } else if (*(short*)endian_test == 1 ) {
    00071     printf_endian(ENDIAN_LITTLE);
    00072   } else {
    00073     printf_endian(ENDIAN_BIG);
    00074   }
    00075   printf("#endif\n");
    00076
    00077   return 0;
    00078 }