dtc: Address an assortment of portability problems

I've recently worked with a FreeBSD developer, getting dtc and libfdt
working on FreeBSD.  This showed up a number of portability problems
in the dtc package which this patch addresses.  Changes are as
follows:

	- the parent_offset and supernode_atdepth_offset testcases
used the glibc extension functions strchrnul() and strndupa().  Those
are removed, using slightly longer coding with standard C functions
instead.

	- some other testcases had a #define _GNU_SOURCE for no
particular reason.  This is removed.

	- run_tests.sh has bash specific constructs removed, and the
interpreter changed to /bin/sh.  This apparently now runs fine on
FreeBSD's /bin/sh, and I've also tested it with both ash and dash.

	- convert-dtsv0-lexer.l has some extra #includes added.  These
must have been included indirectly with Linux and glibc, but aren't on
FreeBSD.

	- the endian handling functions in libfdt_env.h, based on
endian.h and byteswap.h are replaced with some portable open-coded
versions.  Unfortunately, these result in fairly crappy code when
compiled, but as far as I can determine there doesn't seem to be any
POSIX, SUS or de facto standard way of determining endianness at
compile time, nor standard names for byteswapping functions.

	- some more endian handling, from testdata.h using the
problematic endian.h is simply removed, since it wasn't actually being
used anyway.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 14 insertions, 13 deletions

diff --git a/libfdt/libfdt_env.h b/libfdt/libfdt_env.h
index 59f2536..449bf60 100644
--- a/libfdt/libfdt_env.h
+++ b/libfdt/libfdt_env.h
@@ -4,19 +4,20 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
-#include <endian.h>
-#include <byteswap.h>
 
-#if __BYTE_ORDER == __BIG_ENDIAN
-#define fdt32_to_cpu(x)		(x)
-#define cpu_to_fdt32(x)		(x)
-#define fdt64_to_cpu(x)		(x)
-#define cpu_to_fdt64(x)		(x)
-#else
-#define fdt32_to_cpu(x)		(bswap_32((x)))
-#define cpu_to_fdt32(x)		(bswap_32((x)))
-#define fdt64_to_cpu(x)		(bswap_64((x)))
-#define cpu_to_fdt64(x)		(bswap_64((x)))
-#endif
+#define _B(n)	((unsigned long long)((uint8_t *)&x)[n])
+static inline uint32_t fdt32_to_cpu(uint32_t x)
+{
+	return (_B(0) << 24) | (_B(1) << 16) | (_B(2) << 8) | _B(3);
+}
+#define cpu_to_fdt32(x) fdt32_to_cpu(x)
+
+static inline uint64_t fdt64_to_cpu(uint64_t x)
+{
+	return (_B(0) << 56) | (_B(1) << 48) | (_B(2) << 40) | (_B(3) << 32)
+		| (_B(4) << 24) | (_B(5) << 16) | (_B(6) << 8) | _B(7);
+}
+#define cpu_to_fdt64(x) fdt64_to_cpu(x)
+#undef _B
 
 #endif /* _LIBFDT_ENV_H */