OpenTTD-patches/endian_check.c
bjarni 686da2f4e1 (svn r3264) -Codechange: [OSX] OSX targets will now always use the preprocessor to determine endianess
this means that ENDIAN_FORCE is obsolite since it's always overwritten with PREPROCESSOR
	Since the preprocessor should never be able to pick wrong, it's easier this way
	specially when compiling universal binaries as they got both endianess
2005-12-06 14:35:10 +00:00

53 lines
1.6 KiB
C

/* $Id$ */
#include <stdio.h>
// This pretty simple file checks if the system is LITTLE_ENDIAN or BIG_ENDIAN
// it does that by putting a 1 and a 0 in an array, and read it out as one
// number. If it is 1, it is LITTLE_ENDIAN, if it is 256, it is BIG_ENDIAN
//
// After that it outputs the contents of an include files (endian.h)
// that says or TTD_LITTLE_ENDIAN, or TTD_BIG_ENDIAN. Makefile takes
// care of the real writing to the file.
int main (int argc, char *argv[]) {
unsigned char EndianTest[2] = { 1, 0 };
int force_BE = 0, force_LE = 0, force_PREPROCESSOR = 0;
if (argc > 1 && strcmp(argv[1], "BE") == 0)
force_BE = 1;
if (argc > 1 && strcmp(argv[1], "LE") == 0)
force_LE = 1;
if (argc > 1 && strcmp(argv[1], "PREPROCESSOR") == 0)
force_PREPROCESSOR = 1;
printf("#ifndef ENDIAN_H\n#define ENDIAN_H\n");
if (force_LE == 1) {
printf("#define TTD_LITTLE_ENDIAN\n");
} else {
if (force_BE == 1) {
printf("#define TTD_BIG_ENDIAN\n");
} else {
if (force_PREPROCESSOR == 1) {
// adding support for universal binaries on OSX
// Universal binaries supports both PPC and x86
// If a compiler for OSX gets this setting, it will always pick the correct endian and no test is needed
printf("#ifdef __BIG_ENDIAN__\n");
printf("#define TTD_BIG_ENDIAN\n");
printf("#else\n");
printf("#define TTD_LITTLE_ENDIAN\n");
printf("#endif\n");
} else {
if ( *(short *) EndianTest == 1 )
printf("#define TTD_LITTLE_ENDIAN\n");
else
printf("#define TTD_BIG_ENDIAN\n");
}
}
}
printf("#endif\n");
return 0;
}