glibc/sysdeps/unix/i386/sysdep.S

/* Copyright (C) 1991, 1992, 1993, 1994, 1995 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., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <sysdep.h>
#define _ERRNO_H
#include <errnos.h>

.globl C_SYMBOL_NAME(errno)
.globl syscall_error

#undef syscall_error
#ifdef NO_UNDERSCORES
__syscall_error:
#else
syscall_error:
#endif
#if defined (EWOULDBLOCK_sys) && EWOULDBLOCK_sys != EAGAIN
	/* We translate the system's EWOULDBLOCK error into EAGAIN.
	   The GNU C library always defines EWOULDBLOCK==EAGAIN.
	   EWOULDBLOCK_sys is the original number.  */
	cmpl $EWOULDBLOCK_sys, %eax /* Is it the old EWOULDBLOCK?  */
	jne notb		/* Branch if not.  */
	movl $EAGAIN, %eax	/* Yes; translate it to EAGAIN.  */
#endif
notb:
#ifndef	PIC
	movl %eax, C_SYMBOL_NAME(errno)
#else
	/* The caller has pushed %ebx and then set it up to
	   point to the GOT before calling us through the PLT.  */
	movl C_SYMBOL_NAME(errno@GOT)(%ebx), %ecx
	/* Pop %ebx value saved before jumping here.  */
	popl %ebx
	movl %eax, (%ecx)
#endif
	movl $-1, %eax
	ret