tron@2186: /* $Id$ */
tron@2186: 
belugas@6125: /** @file endian_check.cpp
belugas@6125:  * This pretty simple file checks if the system is LITTLE_ENDIAN or BIG_ENDIAN
belugas@6125:  *  it does that by putting a 1 and a 0 in an array, and read it out as one
belugas@6125:  *  number. If it is 1, it is LITTLE_ENDIAN, if it is 256, it is BIG_ENDIAN
belugas@6125:  *
belugas@6125:  * After that it outputs the contents of an include files (endian.h)
belugas@6125:  *  that says or TTD_LITTLE_ENDIAN, or TTD_BIG_ENDIAN. Makefile takes
belugas@6125:  *  care of the real writing to the file. */
belugas@6125: 
truelight@157: #include <stdio.h>
rubidium@5587: #include <string.h>
truelight@157: 
smatz@9543: /** Supported endian types */
smatz@9543: enum Endian {
smatz@9543: 	ENDIAN_LITTLE, ///< little endian
smatz@9543: 	ENDIAN_BIG     ///< big endian
smatz@9543: };
smatz@9543: 
smatz@9543: /**
smatz@9551:  * Shortcut to printf("#define TTD_ENDIAN TTD_*_ENDIAN")
smatz@9543:  * @param endian endian type to define
smatz@9543:  */
smatz@9543: static inline void printf_endian(Endian endian)
smatz@9543: {
smatz@9543: 	printf("#define TTD_ENDIAN %s\n", endian == ENDIAN_LITTLE ? "TTD_LITTLE_ENDIAN" : "TTD_BIG_ENDIAN");
smatz@9543: }
smatz@9543: 
rubidium@7321: /**
rubidium@7321:  * Main call of the endian_check program
belugas@6432:  * @param argc argument count
belugas@6432:  * @param argv arguments themselves
rubidium@7321:  * @return exit code
rubidium@7321:  */
rubidium@7321: int main (int argc, char *argv[])
rubidium@7321: {
rubidium@7321: 	unsigned char endian_test[2] = { 1, 0 };
bjarni@2719: 	int force_BE = 0, force_LE = 0, force_PREPROCESSOR = 0;
TrueLight@1692: 
rubidium@7321: 	if (argc > 1 && strcmp(argv[1], "BE") == 0) force_BE = 1;
rubidium@7321: 	if (argc > 1 && strcmp(argv[1], "LE") == 0) force_LE = 1;
rubidium@7321: 	if (argc > 1 && strcmp(argv[1], "PREPROCESSOR") == 0) force_PREPROCESSOR = 1;
TrueLight@1692: 
bjarni@2713: 	printf("#ifndef ENDIAN_H\n#define ENDIAN_H\n");
truelight@157: 
bjarni@2713: 	if (force_LE == 1) {
smatz@9543: 		printf_endian(ENDIAN_LITTLE);
rubidium@7321: 	} else if (force_BE == 1) {
smatz@9543: 		printf_endian(ENDIAN_BIG);
rubidium@7321: 	} else if (force_PREPROCESSOR == 1) {
rubidium@7321: 		/* Support for universal binaries on OSX
rubidium@7321: 		 * Universal binaries supports both PPC and x86
rubidium@7321: 		 * If a compiler for OSX gets this setting, it will always pick the correct endian and no test is needed
rubidium@7321: 		 */
rubidium@7321: 		printf("#ifdef __BIG_ENDIAN__\n");
smatz@9543: 		printf_endian(ENDIAN_BIG);
rubidium@7321: 		printf("#else\n");
smatz@9543: 		printf_endian(ENDIAN_LITTLE);
rubidium@7321: 		printf("#endif\n");
rubidium@7321: 	} else if (*(short*)endian_test == 1 ) {
smatz@9543: 		printf_endian(ENDIAN_LITTLE);
bjarni@2713: 	} else {
smatz@9543: 		printf_endian(ENDIAN_BIG);
bjarni@2713: 	}
bjarni@2713: 	printf("#endif\n");
truelight@157: 
bjarni@2713: 	return 0;
truelight@157: }