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/* Copyright (C) 1997 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef _NETINET_IN_H
# error "Don't include this file directly, use <netinet/in.h>"
#endif
#if defined __GNUC__ && __GNUC__ >= 2
/* We can use inline assembler instructions to optimize the code. */
/* To swap the bytes in a word the i486 processors and up provide the
`bswap' opcode. On i386 we have to use three instructions. */
# if !defined __i486__ && !defined __pentium__ && !defined __pentiumpro__
extern __inline u_int32_t
__ntohl (u_int32_t netlong)
{
register u_int32_t hostlong;
__asm__ ("rorw $8, %w0; rorl $16, %0; rorw $8, %w0"
: "=r" (hostlong)
: "0" (netlong));
return hostlong;
}
# else
extern __inline u_int32_t
__ntohl (u_int32_t netlong)
{
register u_int32_t hostlong;
__asm__ ("bswap %0" : "=r" (hostlong) : "0" (netlong));
return hostlong;
}
# endif
/* For a short word we have a simple solution. */
extern __inline u_int16_t
__ntohs (u_int16_t netshort)
{
register u_int16_t hostshort;
__asm__ ("rorw $8, %w0" : "=r" (hostshort) : "0" (netshort));
}
/* The other direction can be handled with the same functions. */
extern __inline u_int32_t
__htonl (u_int32_t hostlong)
{
return __ntohl (hostlong);
}
extern __inline u_int16_t
__htons (u_int16_t hostshort)
{
return __ntohs (hostshort);
}
#endif /* GNU CC */
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