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authorManoj Srivastava <srivasta@golden-gryphon.com>2014-04-27 18:05:39 -0700
committerManoj Srivastava <srivasta@golden-gryphon.com>2014-04-27 18:05:39 -0700
commit7d4c02d5c9108aa413fbb0ffa1dc8a39bc5f54a1 (patch)
tree2abb9ad01d397bc1e208f57f528c1ec529761392 /mcon/U/byteorder.U
parent5c913c35c09a82eead2c07534baa709a5dead3e7 (diff)
parent8f5e5726134ce5b4bd436b16f367796d851df553 (diff)
Merge branch 'upstream'
Signed-off-by: Manoj Srivastava <srivasta@golden-gryphon.com> Conflicts: jmake/jmake.man
Diffstat (limited to 'mcon/U/byteorder.U')
-rw-r--r--mcon/U/byteorder.U123
1 files changed, 46 insertions, 77 deletions
diff --git a/mcon/U/byteorder.U b/mcon/U/byteorder.U
index a2242c5..8989838 100644
--- a/mcon/U/byteorder.U
+++ b/mcon/U/byteorder.U
@@ -1,99 +1,68 @@
-?RCS: $Id: byteorder.U 1 2006-08-24 12:32:52Z rmanfredi $
?RCS:
-?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi
+?RCS: Copyright (c) 1991-1997, 2004-2006, 2012 Raphael Manfredi
?RCS:
-?RCS: You may redistribute only under the terms of the Artistic Licence,
+?RCS: You may redistribute only under the terms of the Artistic License,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
-?RCS: that same Artistic Licence; a copy of which may be found at the root
+?RCS: that same Artistic License; a copy of which may be found at the root
?RCS: of the source tree for dist 4.0.
?RCS:
-?RCS: $Log: byteorder.U,v $
-?RCS: Revision 3.0.1.2 1997/02/28 15:24:55 ram
-?RCS: patch61: no longer ask the user if the test runs ok
-?RCS:
-?RCS: Revision 3.0.1.1 1994/10/29 16:02:58 ram
-?RCS: patch36: added ?F: line for metalint file checking
-?RCS:
-?RCS: Revision 3.0 1993/08/18 12:05:28 ram
-?RCS: Baseline for dist 3.0 netwide release.
-?RCS:
-?MAKE:byteorder: cat Myread Oldconfig Loc +cc +ccflags rm
+?MAKE:byteorder: cat contains echo n c Myread Oldconfig Loc +cc +ccflags rm _o
?MAKE: -pick add $@ %<
?S:byteorder:
?S: This variable holds the byte order. In the following, larger digits
?S: indicate more significance. The variable byteorder is either 4321
-?S: on a big-endian machine, or 1234 on a little-endian, or 87654321
-?S: on a Cray ... or 3412 with weird order !
+?S: on a big-endian machine, or 1234 on a little-endian one.
+?S: cannot figure it out.
?S:.
?C:BYTEORDER:
-?C: This symbol hold the hexadecimal constant defined in byteorder,
-?C: i.e. 0x1234 or 0x4321, etc...
+?C: This symbol holds the hexadecimal constant defined in byteorder,
+?C: i.e. 1234 for little-endian or 4321 for big-ending.
?C:.
?H:#define BYTEORDER 0x$byteorder /* large digits for MSB */
?H:.
-?T:xxx_prompt
-?F:!try
-: check for ordering of bytes in a long
-case "$byteorder" in
-'')
- $cat <<'EOM'
-
-In the following, larger digits indicate more significance. A big-endian
-machine like a Pyramid or a Motorola 680?0 chip will come out to 4321. A
-little-endian machine like a Vax or an Intel 80?86 chip would be 1234. Other
-machines may have weird orders like 3412. A Cray will report 87654321. If
-the test program works the default is probably right.
-I'm now running the test program...
-EOM
- $cat >try.c <<'EOCP'
-#include <stdio.h>
-int main()
-{
- int i;
- union {
- unsigned long l;
- char c[sizeof(long)];
- } u;
-
- if (sizeof(long) > 4)
- u.l = (0x08070605L << 32) | 0x04030201L;
- else
- u.l = 0x04030201L;
- for (i = 0; i < sizeof(long); i++)
- printf("%c", u.c[i]+'0');
- printf("\n");
- exit(0);
-}
+?T:order
+: check for ordering of bytes in a word
+?X:
+?X: An idea from Guido Draheim <Guido.Draheim@gmx.de> checking the endianness
+?X: without actually executing code, which allows cross-compiling.
+?X:
+echo " "
+$echo $n "Checking integer byte-ordering...$c" >&4
+$cat >try.c <<'EOCP'
+short ascii_be[] = { 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 0x7953, 0 };
+short ascii_le[] = { 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 0x6E61, 0 };
+short ebcdic_be[] = { 0xC2C9, 0xC785, 0x95C4, 0x8981, 0x95E2, 0xA8E2, 0 };
+short ebcdic_le[] = { 0x89D3, 0xE3E3, 0x8593, 0x95C5, 0x89C4, 0x9581, 0 };
EOCP
- xxx_prompt=y
- if $cc $ccflags -o try try.c >/dev/null 2>&1 && ./try > /dev/null; then
- dflt=`./try`
- case "$dflt" in
- [1-4][1-4][1-4][1-4]|12345678|87654321)
- echo "(The test program ran ok.)"
- echo "byteorder=$dflt"
- xxx_prompt=n
- ;;
- ????|????????) echo "(The test program ran ok.)" ;;
- *) echo "(The test program didn't run right for some reason.)" ;;
- esac
+order=''
+if $cc -c $ccflags try.c >/dev/null 2>&1; then
+ if $contains BIGenDianSyS try$_o >/dev/null 2>&1; then
+ order=4321
+ elif $contains LiTTleEnDian try$_o >/dev/null 2>&1; then
+ order=1234
else
- dflt='4321'
- cat <<'EOM'
-(I can't seem to compile the test program. Guessing big-endian...)
-EOM
+ $echo $n " wild guessing$c" >&4
+ order=4321
fi
- case "$xxx_prompt" in
- y)
- rp="What is the order of bytes in a long?"
- . ./myread
- byteorder="$ans"
- ;;
- *) byteorder=$dflt
- ;;
+fi
+case "$order" in
+'')
+ echo " cannot compute it." >&4
+ rp="Are integers stored in big-endian format?"
+ case "$byteorder" in
+ 1234) dflt=n;;
+ *) dflt=y;;
+ esac
+ . ./myread
+ case "$ans" in
+ y*) order=4321;;
+ *) order=1234;;
esac
;;
+1234) echo " little-endian." >&4;;
+4321) echo " big-endian." >&4;;
esac
-$rm -f try.c try
+byteorder=$order
+$rm -f try.c try$_o