glibc/sysdeps/unix/sysdep.h

76 lines
2.7 KiB
C

/* Copyright (C) 1991-2015 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)
/* Cancellation macros. */
#define __SYSCALL_NARGS_X(a,b,c,d,e,f,g,n,...) n
#define __SYSCALL_NARGS(...) \
__SYSCALL_NARGS_X (__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0,)
#define SYSCALL_CANCEL(name, ...) \
({ \
long int sc_ret; \
if (SINGLE_THREAD_P) \
sc_ret = INLINE_SYSCALL (name, __SYSCALL_NARGS(__VA_ARGS__), \
__VA_ARGS__); \
else \
{ \
int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
sc_ret = INLINE_SYSCALL (name, __SYSCALL_NARGS (__VA_ARGS__), \
__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