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authorJörg Frings-Fürst <debian@jff-webhosting.net>2014-10-06 14:00:40 +0200
committerJörg Frings-Fürst <debian@jff-webhosting.net>2014-10-06 14:00:40 +0200
commit6e9c41a892ed0e0da326e0278b3221ce3f5713b8 (patch)
tree2e301d871bbeeb44aa57ff9cc070fcf3be484487 /m4/byteorder.m4
Initial import of sane-backends version 1.0.24-1.2
Diffstat (limited to 'm4/byteorder.m4')
-rw-r--r--m4/byteorder.m4401
1 files changed, 401 insertions, 0 deletions
diff --git a/m4/byteorder.m4 b/m4/byteorder.m4
new file mode 100644
index 0000000..c8b91d3
--- /dev/null
+++ b/m4/byteorder.m4
@@ -0,0 +1,401 @@
+dnl AC_NEED_BYTEORDER_H ( HEADER-TO-GENERATE )
+dnl Copyright 2001-2002 by Dan Fandrich <dan@coneharvesters.com>
+dnl This file may be copied and used freely without restrictions. No warranty
+dnl is expressed or implied.
+dnl
+dnl Create a header file that guarantees that byte swapping macros of the
+dnl ntohl variety as well as the extended types included in OpenBSD and
+dnl NetBSD such as le32toh are defined. If possible, the standard ntohl
+dnl are overloaded as they are optimized for the given platform, but when
+dnl this is not possible (e.g. on a big-endian machine) they are defined
+dnl in this file.
+
+dnl Look for a symbol in a header file
+dnl AC_HAVE_SYMBOL ( IDENTIFIER, HEADER-FILE, ACTION-IF-FOUND, ACTION-IF-NOT-FOUND )
+AC_DEFUN([AC_HAVE_SYMBOL],
+[
+AC_MSG_CHECKING(for $1 in $2)
+AC_EGREP_CPP([symbol is present|\<$1\>],[
+#include <$2>
+#ifdef $1
+ symbol is present
+#endif
+ ],
+[AC_MSG_RESULT(yes)
+$3
+],
+[AC_MSG_RESULT(no)
+$4
+])])
+
+
+dnl Create a header file that defines extended byte swapping macros
+AC_DEFUN([AC_NEED_BYTEORDER_H],
+[
+ac_byteorder_h=`echo ifelse($1, , _byteorder.h, $1)`
+changequote(, )dnl
+ac_dir=`echo $ac_byteorder_h|sed 's%/[^/][^/]*$%%'`
+changequote([, ])dnl
+if test "$ac_dir" != "$ac_byteorder" && test "$ac_dir" != .; then
+ # The file is in a subdirectory.
+ test ! -d "$ac_dir" && mkdir "$ac_dir"
+fi
+
+# We're only interested in the target CPU, but it's not always set
+effective_target="$target"
+if test "x$effective_target" = xNONE -o "x$effective_target" = x ; then
+ effective_target="$host"
+fi
+AC_SUBST(effective_target)
+
+ac_byteorder=_byteorder.tmp
+cat > "$ac_byteorder" << EOF
+/* This file is generated automatically by configure */
+/* It is valid only for the system type ${effective_target} */
+
+#ifndef __BYTEORDER_H
+#define __BYTEORDER_H
+
+EOF
+
+dnl First, do an endian check
+AC_C_BIGENDIAN
+
+dnl Look for NetBSD-style extended byte swapping macros
+AC_HAVE_SYMBOL(le32toh,machine/endian.h,
+ [HAVE_LE32TOH=1
+ cat >> "$ac_byteorder" << EOF
+/* extended byte swapping macros are already available */
+#include <machine/endian.h>
+
+EOF],
+
+[
+
+dnl Look for standard byte swapping macros
+AC_HAVE_SYMBOL(ntohl,arpa/inet.h,
+ [cat >> "$ac_byteorder" << EOF
+/* ntohl and relatives live here */
+#include <arpa/inet.h>
+
+EOF],
+
+ [AC_HAVE_SYMBOL(ntohl,netinet/in.h,
+ [cat >> "$ac_byteorder" << EOF
+/* ntohl and relatives live here */
+#include <netinet/in.h>
+
+EOF],true)])
+])
+
+dnl Look for generic byte swapping macros
+
+dnl OpenBSD
+AC_HAVE_SYMBOL(swap32,machine/endian.h,
+ [cat >> "$ac_byteorder" << EOF
+/* swap32 and swap16 are defined in machine/endian.h */
+
+EOF],
+
+ [
+dnl Linux GLIBC
+ AC_HAVE_SYMBOL(bswap_32,byteswap.h,
+ [cat >> "$ac_byteorder" << EOF
+/* Define generic byte swapping functions */
+#include <byteswap.h>
+#define swap16(x) bswap_16(x)
+#define swap32(x) bswap_32(x)
+#define swap64(x) bswap_64(x)
+
+EOF],
+
+ [
+dnl NetBSD
+ AC_HAVE_SYMBOL(bswap32,machine/endian.h,
+ dnl We're already including machine/endian.h if this test succeeds
+ [cat >> "$ac_byteorder" << EOF
+/* Define generic byte swapping functions */
+EOF
+ if test "$HAVE_LE32TOH" != "1"; then
+ echo '#include <machine/endian.h>'>> "$ac_byteorder"
+ fi
+cat >> "$ac_byteorder" << EOF
+#define swap16(x) bswap16(x)
+#define swap32(x) bswap32(x)
+#define swap64(x) bswap64(x)
+
+EOF],
+
+ [
+dnl FreeBSD
+ AC_HAVE_SYMBOL(__byte_swap_long,sys/types.h,
+ [cat >> "$ac_byteorder" << EOF
+/* Define generic byte swapping functions */
+#include <sys/types.h>
+#define swap16(x) __byte_swap_word(x)
+#define swap32(x) __byte_swap_long(x)
+/* No optimized 64 bit byte swapping macro is available */
+#define swap64(x) ((uint64_t)(((uint64_t)(x) << 56) & 0xff00000000000000ULL | \\
+ ((uint64_t)(x) << 40) & 0x00ff000000000000ULL | \\
+ ((uint64_t)(x) << 24) & 0x0000ff0000000000ULL | \\
+ ((uint64_t)(x) << 8) & 0x000000ff00000000ULL | \\
+ ((x) >> 8) & 0x00000000ff000000ULL | \\
+ ((x) >> 24) & 0x0000000000ff0000ULL | \\
+ ((x) >> 40) & 0x000000000000ff00ULL | \\
+ ((x) >> 56) & 0x00000000000000ffULL))
+
+EOF],
+
+ [
+dnl OS X
+ AC_HAVE_SYMBOL(NXSwapLong,machine/byte_order.h,
+ [cat >> "$ac_byteorder" << EOF
+/* Define generic byte swapping functions */
+#include <machine/byte_order.h>
+#define swap16(x) NXSwapShort(x)
+#define swap32(x) NXSwapLong(x)
+#define swap64(x) NXSwapLongLong(x)
+
+EOF],
+ [
+ if test $ac_cv_c_bigendian = yes; then
+ cat >> "$ac_byteorder" << EOF
+/* No other byte swapping functions are available on this big-endian system */
+#define swap16(x) ((uint16_t)(((x) << 8) | ((uint16_t)(x) >> 8)))
+#define swap32(x) ((uint32_t)(((uint32_t)(x) << 24) & 0xff000000UL | \\
+ ((uint32_t)(x) << 8) & 0x00ff0000UL | \\
+ ((x) >> 8) & 0x0000ff00UL | \\
+ ((x) >> 24) & 0x000000ffUL))
+#define swap64(x) ((uint64_t)(((uint64_t)(x) << 56) & 0xff00000000000000ULL | \\
+ ((uint64_t)(x) << 40) & 0x00ff000000000000ULL | \\
+ ((uint64_t)(x) << 24) & 0x0000ff0000000000ULL | \\
+ ((uint64_t)(x) << 8) & 0x000000ff00000000ULL | \\
+ ((x) >> 8) & 0x00000000ff000000ULL | \\
+ ((x) >> 24) & 0x0000000000ff0000ULL | \\
+ ((x) >> 40) & 0x000000000000ff00ULL | \\
+ ((x) >> 56) & 0x00000000000000ffULL))
+
+EOF
+ else
+ cat >> "$ac_byteorder" << EOF
+/* Use these as generic byteswapping macros on this little endian system */
+#define swap16(x) ntohs(x)
+#define swap32(x) ntohl(x)
+/* No optimized 64 bit byte swapping macro is available */
+#define swap64(x) ((uint64_t)(((uint64_t)(x) << 56) & 0xff00000000000000ULL | \\
+ ((uint64_t)(x) << 40) & 0x00ff000000000000ULL | \\
+ ((uint64_t)(x) << 24) & 0x0000ff0000000000ULL | \\
+ ((uint64_t)(x) << 8) & 0x000000ff00000000ULL | \\
+ ((x) >> 8) & 0x00000000ff000000ULL | \\
+ ((x) >> 24) & 0x0000000000ff0000ULL | \\
+ ((x) >> 40) & 0x000000000000ff00ULL | \\
+ ((x) >> 56) & 0x00000000000000ffULL))
+
+EOF
+ fi
+])
+ ])
+ ])
+ ])
+])
+
+
+[
+if test "$HAVE_LE32TOH" != "1"; then
+ cat >> "$ac_byteorder" << EOF
+/* The byte swapping macros have the form: */
+/* EENN[a]toh or htoEENN[a] where EE is be (big endian) or */
+/* le (little-endian), NN is 16 or 32 (number of bits) and a, */
+/* if present, indicates that the endian side is a pointer to an */
+/* array of uint8_t bytes instead of an integer of the specified length. */
+/* h refers to the host's ordering method. */
+
+/* So, to convert a 32-bit integer stored in a buffer in little-endian */
+/* format into a uint32_t usable on this machine, you could use: */
+/* uint32_t value = le32atoh(&buf[3]); */
+/* To put that value back into the buffer, you could use: */
+/* htole32a(&buf[3], value); */
+
+/* Define aliases for the standard byte swapping macros */
+/* Arguments to these macros must be properly aligned on natural word */
+/* boundaries in order to work properly on all architectures */
+#ifndef htobe16
+#define htobe16(x) htons(x)
+#endif
+#ifndef htobe32
+#define htobe32(x) htonl(x)
+#endif
+#ifndef be16toh
+#define be16toh(x) ntohs(x)
+#endif
+#ifndef be32toh
+#define be32toh(x) ntohl(x)
+#endif
+
+#define HTOBE16(x) (x) = htobe16(x)
+#define HTOBE32(x) (x) = htobe32(x)
+#define BE32TOH(x) (x) = be32toh(x)
+#define BE16TOH(x) (x) = be16toh(x)
+
+EOF
+
+ if test $ac_cv_c_bigendian = yes; then
+ cat >> "$ac_byteorder" << EOF
+/* Define our own extended byte swapping macros for big-endian machines */
+#ifndef htole16
+#define htole16(x) swap16(x)
+#endif
+#ifndef htole32
+#define htole32(x) swap32(x)
+#endif
+#ifndef le16toh
+#define le16toh(x) swap16(x)
+#endif
+#ifndef le32toh
+#define le32toh(x) swap32(x)
+#endif
+
+#ifndef htobe64
+#define htobe64(x) (x)
+#endif
+#ifndef be64toh
+#define be64toh(x) (x)
+#endif
+
+#define HTOLE16(x) (x) = htole16(x)
+#define HTOLE32(x) (x) = htole32(x)
+#define LE16TOH(x) (x) = le16toh(x)
+#define LE32TOH(x) (x) = le32toh(x)
+
+#define HTOBE64(x) (void) (x)
+#define BE64TOH(x) (void) (x)
+
+EOF
+ else
+ cat >> "$ac_byteorder" << EOF
+/* On little endian machines, these macros are null */
+#ifndef htole16
+#define htole16(x) (x)
+#endif
+#ifndef htole32
+#define htole32(x) (x)
+#endif
+#ifndef htole64
+#define htole64(x) (x)
+#endif
+#ifndef le16toh
+#define le16toh(x) (x)
+#endif
+#ifndef le32toh
+#define le32toh(x) (x)
+#endif
+#ifndef le64toh
+#define le64toh(x) (x)
+#endif
+
+#define HTOLE16(x) (void) (x)
+#define HTOLE32(x) (void) (x)
+#define HTOLE64(x) (void) (x)
+#define LE16TOH(x) (void) (x)
+#define LE32TOH(x) (void) (x)
+#define LE64TOH(x) (void) (x)
+
+/* These don't have standard aliases */
+#ifndef htobe64
+#define htobe64(x) swap64(x)
+#endif
+#ifndef be64toh
+#define be64toh(x) swap64(x)
+#endif
+
+#define HTOBE64(x) (x) = htobe64(x)
+#define BE64TOH(x) (x) = be64toh(x)
+
+EOF
+ fi
+fi
+
+cat >> "$ac_byteorder" << EOF
+/* Define the C99 standard length-specific integer types */
+#include <_stdint.h>
+
+EOF
+
+case "${effective_target}" in
+ i[3456]86-*)
+ cat >> "$ac_byteorder" << EOF
+/* Here are some macros to create integers from a byte array */
+/* These are used to get and put integers from/into a uint8_t array */
+/* with a specific endianness. This is the most portable way to generate */
+/* and read messages to a network or serial device. Each member of a */
+/* packet structure must be handled separately. */
+
+/* The i386 and compatibles can handle unaligned memory access, */
+/* so use the optimized macros above to do this job */
+#define be16atoh(x) be16toh(*(uint16_t*)(x))
+#define be32atoh(x) be32toh(*(uint32_t*)(x))
+#define be64atoh(x) be64toh(*(uint64_t*)(x))
+#define le16atoh(x) le16toh(*(uint16_t*)(x))
+#define le32atoh(x) le32toh(*(uint32_t*)(x))
+#define le64atoh(x) le64toh(*(uint64_t*)(x))
+
+#define htobe16a(a,x) *(uint16_t*)(a) = htobe16(x)
+#define htobe32a(a,x) *(uint32_t*)(a) = htobe32(x)
+#define htobe64a(a,x) *(uint64_t*)(a) = htobe64(x)
+#define htole16a(a,x) *(uint16_t*)(a) = htole16(x)
+#define htole32a(a,x) *(uint32_t*)(a) = htole32(x)
+#define htole64a(a,x) *(uint64_t*)(a) = htole64(x)
+
+EOF
+ ;;
+
+ *)
+ cat >> "$ac_byteorder" << EOF
+/* Here are some macros to create integers from a byte array */
+/* These are used to get and put integers from/into a uint8_t array */
+/* with a specific endianness. This is the most portable way to generate */
+/* and read messages to a network or serial device. Each member of a */
+/* packet structure must be handled separately. */
+
+/* Non-optimized but portable macros */
+#define be16atoh(x) ((uint16_t)(((x)[0]<<8)|(x)[1]))
+#define be32atoh(x) ((uint32_t)(((x)[0]<<24)|((x)[1]<<16)|((x)[2]<<8)|(x)[3]))
+#define be64atoh(x) ((uint64_t)(((x)[0]<<56)|((x)[1]<<48)|((x)[2]<<40)| \\
+ ((x)[3]<<32)|((x)[4]<<24)|((x)[5]<<16)|((x)[6]<<8)|(x)[7]))
+#define le16atoh(x) ((uint16_t)(((x)[1]<<8)|(x)[0]))
+#define le32atoh(x) ((uint32_t)(((x)[3]<<24)|((x)[2]<<16)|((x)[1]<<8)|(x)[0]))
+#define le64atoh(x) ((uint64_t)(((x)[7]<<56)|((x)[6]<<48)|((x)[5]<<40)| \\
+ ((x)[4]<<32)|((x)[3]<<24)|((x)[2]<<16)|((x)[1]<<8)|(x)[0]))
+
+#define htobe16a(a,x) (a)[0]=(uint8_t)((x)>>8), (a)[1]=(uint8_t)(x)
+#define htobe32a(a,x) (a)[0]=(uint8_t)((x)>>24), (a)[1]=(uint8_t)((x)>>16), \\
+ (a)[2]=(uint8_t)((x)>>8), (a)[3]=(uint8_t)(x)
+#define htobe64a(a,x) (a)[0]=(uint8_t)((x)>>56), (a)[1]=(uint8_t)((x)>>48), \\
+ (a)[2]=(uint8_t)((x)>>40), (a)[3]=(uint8_t)((x)>>32), \\
+ (a)[4]=(uint8_t)((x)>>24), (a)[5]=(uint8_t)((x)>>16), \\
+ (a)[6]=(uint8_t)((x)>>8), (a)[7]=(uint8_t)(x)
+#define htole16a(a,x) (a)[1]=(uint8_t)((x)>>8), (a)[0]=(uint8_t)(x)
+#define htole32a(a,x) (a)[3]=(uint8_t)((x)>>24), (a)[2]=(uint8_t)((x)>>16), \\
+ (a)[1]=(uint8_t)((x)>>8), (a)[0]=(uint8_t)(x)
+#define htole64a(a,x) (a)[7]=(uint8_t)((x)>>56), (a)[6]=(uint8_t)((x)>>48), \\
+ (a)[5]=(uint8_t)((x)>>40), (a)[4]=(uint8_t)((x)>>32), \\
+ (a)[3]=(uint8_t)((x)>>24), (a)[2]=(uint8_t)((x)>>16), \\
+ (a)[1]=(uint8_t)((x)>>8), (a)[0]=(uint8_t)(x)
+
+EOF
+ ;;
+esac
+]
+
+cat >> "$ac_byteorder" << EOF
+#endif /*__BYTEORDER_H*/
+EOF
+
+if cmp -s $ac_byteorder_h $ac_byteorder 2>/dev/null; then
+ AC_MSG_NOTICE([$ac_byteorder_h is unchanged])
+ rm $ac_byteorder
+else
+ rm -f $ac_byteorder_h
+ mv $ac_byteorder $ac_byteorder_h
+fi
+])