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/* Copyright (C) 1992,1993,1995-2000,2002,2003,2004
Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper, <drepper@gnu.org>, August 1995.
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. */
#ifndef _FREEBSD_I386_SYSDEP_H
#define _FREEBSD_I386_SYSDEP_H 1
/* There is some commonality. */
#include <sysdeps/unix/i386/sysdep.h>
/* Defines RTLD_PRIVATE_ERRNO and USE_DL_SYSINFO. */
#include <dl-sysdep.h>
#include <tls.h>
#ifdef __ASSEMBLER__
/* We don't want the label for the error handle to be global when we define
it here. */
#ifdef PIC
# define SYSCALL_ERROR_LABEL 0f
#else
# define SYSCALL_ERROR_LABEL syscall_error
#endif
#undef PSEUDO
#define PSEUDO(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
jb SYSCALL_ERROR_LABEL; \
L(pseudo_end):
#undef PSEUDO_END
#define PSEUDO_END(name) \
SYSCALL_ERROR_HANDLER \
END (name)
#undef PSEUDO_NOERRNO
#define PSEUDO_NOERRNO(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args)
#undef PSEUDO_END_NOERRNO
#define PSEUDO_END_NOERRNO(name) \
END (name)
#define ret_NOERRNO ret
/* The function has to return the error code. */
#undef PSEUDO_ERRVAL
#define PSEUDO_ERRVAL(name, syscall_name, args) \
.text; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
#undef PSEUDO_END_ERRVAL
#define PSEUDO_END_ERRVAL(name) \
END (name)
#define ret_ERRVAL ret
#ifndef PIC
# define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
#else
# if RTLD_PRIVATE_ERRNO
# define SYSCALL_ERROR_HANDLER \
0:SETUP_PIC_REG(cx); \
addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
movl %eax, rtld_errno@GOTOFF(%ecx); \
orl $-1, %eax; \
jmp L(pseudo_end);
# elif defined _LIBC_REENTRANT
# if IS_IN (libc)
# define SYSCALL_ERROR_ERRNO __libc_errno
# else
# define SYSCALL_ERROR_ERRNO errno
# endif
# define SYSCALL_ERROR_HANDLER \
0:SETUP_PIC_REG (cx); \
addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
movl SYSCALL_ERROR_ERRNO@GOTNTPOFF(%ecx), %ecx; \
SYSCALL_ERROR_HANDLER_TLS_STORE (%eax, %ecx); \
orl $-1, %eax; \
jmp L(pseudo_end);
# ifndef NO_TLS_DIRECT_SEG_REFS
# define SYSCALL_ERROR_HANDLER_TLS_STORE(src, destoff) \
movl src, %gs:(destoff)
# else
# define SYSCALL_ERROR_HANDLER_TLS_STORE(src, destoff) \
addl %gs:0, destoff; \
movl src, (destoff)
# endif
# else
/* Store (%eax) into errno through the GOT. */
# define SYSCALL_ERROR_HANDLER \
0:SETUP_PIC_REG(cx); \
addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
movl errno@GOT(%ecx), %ecx; \
movl %eax, (%ecx); \
orl $-1, %eax; \
jmp L(pseudo_end);
# endif /* _LIBC_REENTRANT */
#endif /* PIC */
/*
FreeBSD expects the system call arguments on the stack,
syscall number is in %eax.
return value is in %eax + %edx
error is signaled via cflags.
all other data registers are preserved
syscall number %eax call-clobbered
The stack layout upon entering the function is:
20(%esp) Arg# 5
16(%esp) Arg# 4
12(%esp) Arg# 3
8(%esp) Arg# 2
4(%esp) Arg# 1
(%esp) Return address
(Of course a function with say 3 arguments does not have entries for
arguments 4 and 5.)
*/
#undef DO_CALL
#define DO_CALL(syscall_name, args) \
movl $SYS_ify (syscall_name), %eax; \
int $0x80 \
#else /* !__ASSEMBLER__ */
#include <syscalls-inline.h>
/* Consistency check for position-independent code. */
#if defined __PIC__ && !__GNUC_PREREQ (5,0)
# define check_consistency() \
({ int __res; \
__asm__ __volatile__ \
(LOAD_PIC_REG_STR (cx) ";" \
"subl %%ebx, %%ecx;" \
"je 1f;" \
"ud2;" \
"1:\n" \
: "=c" (__res)); \
__res; })
#endif
#endif /* __ASSEMBLER__ */
/* Pointer mangling support. */
#if IS_IN (rtld)
/* We cannot use the thread descriptor because in ld.so we use setjmp
earlier than the descriptor is initialized. Using a global variable
is too complicated here since we have no PC-relative addressing mode. */
#else
# ifdef __ASSEMBLER__
# define PTR_MANGLE(reg) xorl %gs:POINTER_GUARD, reg; \
roll $9, reg
# define PTR_DEMANGLE(reg) rorl $9, reg; \
xorl %gs:POINTER_GUARD, reg
# else
# define PTR_MANGLE(var) asm ("xorl %%gs:%c2, %0\n" \
"roll $9, %0" \
: "=r" (var) \
: "0" (var), \
"i" (offsetof (tcbhead_t, \
pointer_guard)))
# define PTR_DEMANGLE(var) asm ("rorl $9, %0\n" \
"xorl %%gs:%c2, %0" \
: "=r" (var) \
: "0" (var), \
"i" (offsetof (tcbhead_t, \
pointer_guard)))
# endif
#endif
#endif /* _FREEBSD_I386_SYSDEP_H */
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