--- /dev/null
+dnl @synopsis MN_C_FIND_ENDIAN
+dnl
+dnl Determine endian-ness of target processor.
+dnl @version 1.1 Mar 03 2002
+dnl @author Erik de Castro Lopo <erikd AT mega-nerd DOT com>
+dnl
+dnl Majority written from scratch to replace the standard autoconf macro
+dnl AC_C_BIGENDIAN. Only part remaining from the original it the invocation
+dnl of the AC_TRY_RUN macro.
+dnl
+dnl Permission to use, copy, modify, distribute, and sell this file for any
+dnl purpose is hereby granted without fee, provided that the above copyright
+dnl and this permission notice appear in all copies. No representations are
+dnl made about the suitability of this software for any purpose. It is
+dnl provided "as is" without express or implied warranty.
+
+dnl Find endian-ness in the following way:
+dnl 1) Look in <endian.h>.
+dnl 2) If 1) fails, look in <sys/types.h> and <sys/param.h>.
+dnl 3) If 1) and 2) fails and not cross compiling run a test program.
+dnl 4) If 1) and 2) fails and cross compiling then guess based on target.
+
+AC_DEFUN([MN_C_FIND_ENDIAN],
+[AC_CACHE_CHECK(processor byte ordering,
+ ac_cv_c_byte_order,
+
+# Initialize to unknown
+ac_cv_c_byte_order=unknown
+
+if test x$ac_cv_header_endian_h = xyes ; then
+
+ # First try <endian.h> which should set BYTE_ORDER.
+
+ [AC_TRY_LINK([
+ #include <endian.h>
+ #if BYTE_ORDER != LITTLE_ENDIAN
+ not big endian
+ #endif
+ ], return 0 ;,
+ ac_cv_c_byte_order=little
+ )]
+
+ [AC_TRY_LINK([
+ #include <endian.h>
+ #if BYTE_ORDER != BIG_ENDIAN
+ not big endian
+ #endif
+ ], return 0 ;,
+ ac_cv_c_byte_order=big
+ )]
+
+ fi
+
+if test $ac_cv_c_byte_order = unknown ; then
+
+ [AC_TRY_LINK([
+ #include <sys/types.h>
+ #include <sys/param.h>
+ #if !BYTE_ORDER || !BIG_ENDIAN || !LITTLE_ENDIAN
+ bogus endian macros
+ #endif
+ ], return 0 ;,
+
+ [AC_TRY_LINK([
+ #include <sys/types.h>
+ #include <sys/param.h>
+ #if BYTE_ORDER != LITTLE_ENDIAN
+ not big endian
+ #endif
+ ], return 0 ;,
+ ac_cv_c_byte_order=little
+ )]
+
+ [AC_TRY_LINK([
+ #include <sys/types.h>
+ #include <sys/param.h>
+ #if BYTE_ORDER != LITTLE_ENDIAN
+ not big endian
+ #endif
+ ], return 0 ;,
+ ac_cv_c_byte_order=little
+ )]
+
+ )]
+
+ fi
+
+if test $ac_cv_c_byte_order = unknown ; then
+ if test $cross_compiling = yes ; then
+ # This is the last resort. Try to guess the target processor endian-ness
+ # by looking at the target CPU type.
+ [
+ case "$target_cpu" in
+ alpha* | i?86* | mipsel* | ia64*)
+ ac_cv_c_byte_order=little
+ ;;
+
+ m68* | mips* | powerpc* | hppa* | sparc*)
+ ac_cv_c_byte_order=big
+ ;;
+
+ esac
+ ]
+ else
+ AC_TRY_RUN(
+ [[
+ int main (void)
+ { /* Are we little or big endian? From Harbison&Steele. */
+ union
+ { long l ;
+ char c [sizeof (long)] ;
+ } u ;
+ u.l = 1 ;
+ return (u.c [sizeof (long) - 1] == 1);
+ }
+ ]], , ac_cv_c_byte_order=big,
+ )
+
+ AC_TRY_RUN(
+ [[int main (void)
+ { /* Are we little or big endian? From Harbison&Steele. */
+ union
+ { long l ;
+ char c [sizeof (long)] ;
+ } u ;
+ u.l = 1 ;
+ return (u.c [0] == 1);
+ }]], , ac_cv_c_byte_order=little,
+ )
+ fi
+ fi
+
+)
+
+if test $ac_cv_c_byte_order = big ; then
+ ac_cv_c_big_endian=1
+ ac_cv_c_little_endian=0
+elif test $ac_cv_c_byte_order = little ; then
+ ac_cv_c_big_endian=0
+ ac_cv_c_little_endian=1
+else
+ ac_cv_c_big_endian=0
+ ac_cv_c_little_endian=0
+
+ AC_MSG_WARN([[*****************************************************************]])
+ AC_MSG_WARN([[*** Not able to determine endian-ness of target processor. ]])
+ AC_MSG_WARN([[*** The constants CPU_IS_BIG_ENDIAN and CPU_IS_LITTLE_ENDIAN in ]])
+ AC_MSG_WARN([[*** src/config.h may need to be hand editied. ]])
+ AC_MSG_WARN([[*****************************************************************]])
+ fi
+
+]
+)# MN_C_FIND_ENDIAN
+
+