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/* Wrapper for setting errno.
Copyright (C) 1997, 1998, 1999, 2000 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. */
#include <errno.h>
#include <features.h>
/* This routine is jumped to by all the syscall handlers, to stash
* an error number into errno. */
/* This version uses a lot of magic and relies heavily on x86
* calling convention ... The advantage is that this is the same
* size as the previous __syscall_error() but all the .S functions
* need just one instruction.
*
* Local .S files have to set %eax to the negative errno value
* and then jump to this function. The neglected return to caller
* and return value of -1 is taken care of here so we don't have to
* worry about it in the .S functions.
*
* We have to stash the errno from %eax in a local stack var because
* __set_errno will prob call a function thus clobbering %eax on us.
*/
int attribute_hidden __syscall_error(void)
{
register int edx asm("%edx");
asm("mov %eax, %edx");
asm("negl %edx");
__set_errno(edx);
return -1;
}
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