Add m4/endian.m4 and use it in configure.ac.

1 files changed, 177 insertions, 0 deletions

diff --git a/m4/endian.m4 b/m4/endian.m4
new file mode 100644
index 00000000..87c1f493
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+++ b/m4/endian.m4
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+dnl Copyright (C) 2012  Xiph.org Foundation
+dnl
+dnl Redistribution and use in source and binary forms, with or without
+dnl modification, are permitted provided that the following conditions
+dnl are met:
+dnl
+dnl - Redistributions of source code must retain the above copyright
+dnl notice, this list of conditions and the following disclaimer.
+dnl
+dnl - Redistributions in binary form must reproduce the above copyright
+dnl notice, this list of conditions and the following disclaimer in the
+dnl documentation and/or other materials provided with the distribution.
+dnl
+dnl - Neither the name of the Xiph.org Foundation nor the names of its
+dnl contributors may be used to endorse or promote products derived from
+dnl this software without specific prior written permission.
+dnl
+dnl THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+dnl ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+dnl LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+dnl A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+dnl CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+dnl EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+dnl PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+dnl PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+dnl LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+dnl NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+dnl SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+dnl @synopsis XIPH_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@mega-nerd.com>
+dnl
+dnl Majority written from scratch to replace the standard autoconf macro
+dnl AC_C_BIGENDIAN. Only part remaining from the original is the invocation
+dnl of the AC_TRY_RUN macro.
+dnl
+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([XIPH_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([[*** config.h may need to be hand editied.                        ]])
+	AC_MSG_WARN([[*****************************************************************]])
+	fi
+
+]
+)# XIPH_C_FIND_ENDIAN