freebsd-dev/lib/libc/amd64/SYS.h
Jason Evans e9a89b2196 Undo the ill-conceived breakage of the previous commit and really fix:
For libc_r renamed syscalls, correct symbol naming from
_thread_sys_foo() <-- _foo() to _thread_sys_foo() <-- _foo() <-- foo().  This
is necessary for system calls which libc_r doesn't define foo().

Some weak symbols such as poll() are defined twice.  From what I understand,
depending on one weak symbol or the other to be used is a bad idea.  All
such weak symbols defined in the libc_r-specific code should therefore be
made strong (non-weak?).

Simplify PSEUDO() to not define any weak symbols, since they aren't ever
needed.

alpha/SYS.h:

Correct reversed usage of WEAK_ALIAS(), which has reversed arguments from
__weak_reference().  Also, fix reversal of symbols, so that syscall foo()
is a weak alias for _foo().

Add WEAK_ALIAS() call to PRSYSCALL(), which unlike the i386 version of
PRSYSCALL(), is not defined in terms of PSYSCALL().

Make PSEUDO() equivalent to the i386 version.
2000-01-29 12:50:47 +00:00

99 lines
3.8 KiB
C

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)SYS.h 5.5 (Berkeley) 5/7/91
*
* $FreeBSD$
*/
#include <sys/syscall.h>
#include "DEFS.h"
#define SYSCALL(x) 2: PIC_PROLOGUE; jmp PIC_PLT(HIDENAME(cerror)); \
ENTRY(__CONCAT(_,x)); \
.weak CNAME(x); \
.set CNAME(x),CNAME(__CONCAT(_,x)); \
lea __CONCAT(SYS_,x),%eax; KERNCALL; jb 2b
#define RSYSCALL(x) SYSCALL(x); ret
#define PSEUDO(x,y) ENTRY(__CONCAT(_,x)); \
.weak CNAME(x); \
.set CNAME(x),CNAME(__CONCAT(_,x)); \
lea __CONCAT(SYS_,y), %eax; KERNCALL; ret
/* gas messes up offset -- although we don't currently need it, do for BCS */
#define LCALL(x,y) .byte 0x9a ; .long y; .word x
/*
* Design note:
*
* The macros PSYSCALL() and PRSYSCALL() are intended for use where a
* syscall needs to be renamed in the threaded library. When building
* a normal library, they default to the traditional SYSCALL() and
* RSYSCALL(). This avoids the need to #ifdef _THREAD_SAFE everywhere
* that the renamed function needs to be called.
*/
#ifdef _THREAD_SAFE
/*
* For the thread_safe versions, we prepend _thread_sys_ to the function
* name so that the 'C' wrapper can go around the real name.
*/
#define PSYSCALL(x) 2: PIC_PROLOGUE; jmp PIC_PLT(HIDENAME(cerror)); \
ENTRY(__CONCAT(_thread_sys_,x)); \
.weak CNAME(__CONCAT(_,x)); \
.set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(_thread_sys_,x));\
.weak CNAME(x); \
.set CNAME(x),CNAME(__CONCAT(_,x)); \
lea __CONCAT(SYS_,x),%eax; KERNCALL; jb 2b
#define PRSYSCALL(x) PSYSCALL(x); ret
#define PPSEUDO(x,y) ENTRY(__CONCAT(_thread_sys_,x)); \
lea __CONCAT(SYS_,y), %eax; KERNCALL; ret
#else
/*
* The non-threaded library defaults to traditional syscalls where
* the function name matches the syscall name.
*/
#define PSYSCALL(x) SYSCALL(x)
#define PRSYSCALL(x) RSYSCALL(x)
#define PPSEUDO(x,y) PSEUDO(x,y)
#endif
#ifdef __ELF__
#define KERNCALL int $0x80 /* Faster */
#else
#define KERNCALL LCALL(7,0) /* The old way */
#endif