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/* Copyright (C) 1991-2018 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, see
<http://www.gnu.org/licenses/>. */
#include <sysdeps/generic/sysdep.h>
#include <sys/syscall.h>
#define HAVE_SYSCALLS
/* Note that using a `PASTE' macro loses. */
#define SYSCALL__(name, args) PSEUDO (__##name, name, args)
#define SYSCALL(name, args) PSEUDO (name, name, args)
#define __SYSCALL_CONCAT_X(a,b) a##b
#define __SYSCALL_CONCAT(a,b) __SYSCALL_CONCAT_X (a, b)
#define __INTERNAL_SYSCALL0(name, err) \
INTERNAL_SYSCALL (name, err, 0)
#define __INTERNAL_SYSCALL1(name, err, a1) \
INTERNAL_SYSCALL (name, err, 1, a1)
#define __INTERNAL_SYSCALL2(name, err, a1, a2) \
INTERNAL_SYSCALL (name, err, 2, a1, a2)
#define __INTERNAL_SYSCALL3(name, err, a1, a2, a3) \
INTERNAL_SYSCALL (name, err, 3, a1, a2, a3)
#define __INTERNAL_SYSCALL4(name, err, a1, a2, a3, a4) \
INTERNAL_SYSCALL (name, err, 4, a1, a2, a3, a4)
#define __INTERNAL_SYSCALL5(name, err, a1, a2, a3, a4, a5) \
INTERNAL_SYSCALL (name, err, 5, a1, a2, a3, a4, a5)
#define __INTERNAL_SYSCALL6(name, err, a1, a2, a3, a4, a5, a6) \
INTERNAL_SYSCALL (name, err, 6, a1, a2, a3, a4, a5, a6)
#define __INTERNAL_SYSCALL7(name, err, a1, a2, a3, a4, a5, a6, a7) \
INTERNAL_SYSCALL (name, err, 7, a1, a2, a3, a4, a5, a6, a7)
#define __INTERNAL_SYSCALL_NARGS_X(a,b,c,d,e,f,g,h,n,o,...) o
#define __INTERNAL_SYSCALL_NARGS(...) \
__INTERNAL_SYSCALL_NARGS_X (__VA_ARGS__,7,6,5,4,3,2,1,0,)
#define __INTERNAL_SYSCALL_DISP(b,...) \
__SYSCALL_CONCAT (b,__INTERNAL_SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
/* Issue a syscall defined by syscall number plus any other argument required.
It is similar to INTERNAL_SYSCALL macro, but without the need to pass the
expected argument number as second parameter. */
#define INTERNAL_SYSCALL_CALL(...) \
__INTERNAL_SYSCALL_DISP (__INTERNAL_SYSCALL, __VA_ARGS__)
#define __INLINE_SYSCALL0(name) \
INLINE_SYSCALL (name, 0)
#define __INLINE_SYSCALL1(name, a1) \
INLINE_SYSCALL (name, 1, a1)
#define __INLINE_SYSCALL2(name, a1, a2) \
INLINE_SYSCALL (name, 2, a1, a2)
#define __INLINE_SYSCALL3(name, a1, a2, a3) \
INLINE_SYSCALL (name, 3, a1, a2, a3)
#define __INLINE_SYSCALL4(name, a1, a2, a3, a4) \
INLINE_SYSCALL (name, 4, a1, a2, a3, a4)
#define __INLINE_SYSCALL5(name, a1, a2, a3, a4, a5) \
INLINE_SYSCALL (name, 5, a1, a2, a3, a4, a5)
#define __INLINE_SYSCALL6(name, a1, a2, a3, a4, a5, a6) \
INLINE_SYSCALL (name, 6, a1, a2, a3, a4, a5, a6)
#define __INLINE_SYSCALL7(name, a1, a2, a3, a4, a5, a6, a7) \
INLINE_SYSCALL (name, 7, a1, a2, a3, a4, a5, a6, a7)
#define __INLINE_SYSCALL_NARGS_X(a,b,c,d,e,f,g,h,n,...) n
#define __INLINE_SYSCALL_NARGS(...) \
__INLINE_SYSCALL_NARGS_X (__VA_ARGS__,7,6,5,4,3,2,1,0,)
#define __INLINE_SYSCALL_DISP(b,...) \
__SYSCALL_CONCAT (b,__INLINE_SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
/* Issue a syscall defined by syscall number plus any other argument
required. Any error will be handled using arch defined macros and errno
will be set accordingly.
It is similar to INLINE_SYSCALL macro, but without the need to pass the
expected argument number as second parameter. */
#define INLINE_SYSCALL_CALL(...) \
__INLINE_SYSCALL_DISP (__INLINE_SYSCALL, __VA_ARGS__)
#define SYSCALL_CANCEL(...) \
({ \
long int sc_ret; \
if (SINGLE_THREAD_P) \
sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
else \
{ \
int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
LIBC_CANCEL_RESET (sc_cancel_oldtype); \
} \
sc_ret; \
})
/* Issue a syscall defined by syscall number plus any other argument
required. Any error will be returned unmodified (including errno). */
#define INTERNAL_SYSCALL_CANCEL(...) \
({ \
long int sc_ret; \
if (SINGLE_THREAD_P) \
sc_ret = INTERNAL_SYSCALL_CALL (__VA_ARGS__); \
else \
{ \
int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
sc_ret = INTERNAL_SYSCALL_CALL (__VA_ARGS__); \
LIBC_CANCEL_RESET (sc_cancel_oldtype); \
} \
sc_ret; \
})
/* Machine-dependent sysdep.h files are expected to define the macro
PSEUDO (function_name, syscall_name) to emit assembly code to define the
C-callable function FUNCTION_NAME to do system call SYSCALL_NAME.
r0 and r1 are the system call outputs. MOVE(x, y) should be defined as
an instruction such that "MOVE(r1, r0)" works. ret should be defined
as the return instruction. */
#ifndef SYS_ify
#define SYS_ify(syscall_name) SYS_##syscall_name
#endif
/* Terminate a system call named SYM. This is used on some platforms
to generate correct debugging information. */
#ifndef PSEUDO_END
#define PSEUDO_END(sym)
#endif
#ifndef PSEUDO_END_NOERRNO
#define PSEUDO_END_NOERRNO(sym) PSEUDO_END(sym)
#endif
#ifndef PSEUDO_END_ERRVAL
#define PSEUDO_END_ERRVAL(sym) PSEUDO_END(sym)
#endif
/* Wrappers around system calls should normally inline the system call code.
But sometimes it is not possible or implemented and we use this code. */
#ifndef INLINE_SYSCALL
#define INLINE_SYSCALL(name, nr, args...) __syscall_##name (args)
#endif