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authorEric Andersen <andersen@codepoet.org>2002-03-01 20:46:26 +0000
committerEric Andersen <andersen@codepoet.org>2002-03-01 20:46:26 +0000
commit9cee42f10dbc5b33866ff137b926a74abd7c1a5b (patch)
tree5211131bde7212ae06d98e9779197cece9b552cc /libc/sysdeps/linux/common/bits/byteswap.h
parent5b470cfcc321c5d50b951fa93a769a4a193ccece (diff)
Major rework of the include files to eliminate redundancy
and to better support each arch. This is a really big patch... -Erik
Diffstat (limited to 'libc/sysdeps/linux/common/bits/byteswap.h')
-rw-r--r--libc/sysdeps/linux/common/bits/byteswap.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/common/bits/byteswap.h b/libc/sysdeps/linux/common/bits/byteswap.h
new file mode 100644
index 000000000..38d854013
--- /dev/null
+++ b/libc/sysdeps/linux/common/bits/byteswap.h
@@ -0,0 +1,84 @@
+/* Macros to swap the order of bytes in integer values.
+ Copyright (C) 1997, 1998, 2000, 2001, 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#if !defined _BYTESWAP_H && !defined _NETINET_IN_H
+# error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
+#endif
+
+#ifndef _BITS_BYTESWAP_H
+#define _BITS_BYTESWAP_H 1
+
+/* Swap bytes in 16 bit value. */
+#ifdef __GNUC__
+# define __bswap_16(x) \
+ (__extension__ \
+ ({ unsigned short int __bsx = (x); \
+ ((((__bsx) >> 8) & 0xff) | (((__bsx) & 0xff) << 8)); }))
+#else
+static __inline unsigned short int
+__bswap_16 (unsigned short int __bsx)
+{
+ return ((((__bsx) >> 8) & 0xff) | (((__bsx) & 0xff) << 8));
+}
+#endif
+
+/* Swap bytes in 32 bit value. */
+#ifdef __GNUC__
+# define __bswap_32(x) \
+ (__extension__ \
+ ({ unsigned int __bsx = (x); \
+ ((((__bsx) & 0xff000000) >> 24) | (((__bsx) & 0x00ff0000) >> 8) | \
+ (((__bsx) & 0x0000ff00) << 8) | (((__bsx) & 0x000000ff) << 24)); }))
+#else
+static __inline unsigned int
+__bswap_32 (unsigned int __bsx)
+{
+ return ((((__bsx) & 0xff000000) >> 24) | (((__bsx) & 0x00ff0000) >> 8) |
+ (((__bsx) & 0x0000ff00) << 8) | (((__bsx) & 0x000000ff) << 24));
+}
+#endif
+
+#if defined __GNUC__ && __GNUC__ >= 2
+/* Swap bytes in 64 bit value. */
+# define __bswap_constant_64(x) \
+ ((((x) & 0xff00000000000000ull) >> 56) \
+ | (((x) & 0x00ff000000000000ull) >> 40) \
+ | (((x) & 0x0000ff0000000000ull) >> 24) \
+ | (((x) & 0x000000ff00000000ull) >> 8) \
+ | (((x) & 0x00000000ff000000ull) << 8) \
+ | (((x) & 0x0000000000ff0000ull) << 24) \
+ | (((x) & 0x000000000000ff00ull) << 40) \
+ | (((x) & 0x00000000000000ffull) << 56))
+
+# define __bswap_64(x) \
+ (__extension__ \
+ ({ union { __extension__ unsigned long long int __ll; \
+ unsigned int __l[2]; } __w, __r; \
+ if (__builtin_constant_p (x)) \
+ __r.__ll = __bswap_constant_64 (x); \
+ else \
+ { \
+ __w.__ll = (x); \
+ __r.__l[0] = __bswap_32 (__w.__l[1]); \
+ __r.__l[1] = __bswap_32 (__w.__l[0]); \
+ } \
+ __r.__ll; }))
+#endif
+
+#endif /* _BITS_BYTESWAP_H */