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#ifndef _BITS_SYSCALLS_H
#define _BITS_SYSCALLS_H
#ifndef _SYSCALL_H
# error "Never use <bits/syscalls.h> directly; include <sys/syscall.h> instead."
#endif
/* This includes the `__NR_<name>' syscall numbers taken from the Linux kernel
* header files. It also defines the traditional `SYS_<name>' macros for older
* programs. */
#include <bits/sysnum.h>
#ifndef __set_errno
# define __set_errno(val) (*__errno_location ()) = (val)
#endif
/*
Some of the sneaky macros in the code were taken from
glibc-2.2.5/sysdeps/unix/sysv/linux/m68k/sysdep.h
*/
#ifndef __ASSEMBLER__
#undef _syscall0
#define _syscall0(type,name) \
type name(void) \
{ \
return (type) (INLINE_SYSCALL(name, 0)); \
}
#undef _syscall1
#define _syscall1(type,name,type1,arg1) \
type name(type1 arg1) \
{ \
return (type) (INLINE_SYSCALL(name, 1, arg1)); \
}
#undef _syscall2
#define _syscall2(type,name,type1,arg1,type2,arg2) \
type name(type1 arg1,type2 arg2) \
{ \
return (type) (INLINE_SYSCALL(name, 2, arg1, arg2)); \
}
#undef _syscall3
#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \
type name(type1 arg1,type2 arg2,type3 arg3) \
{ \
return (type) (INLINE_SYSCALL(name, 3, arg1, arg2, arg3)); \
}
#undef _syscall4
#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \
type name (type1 arg1, type2 arg2, type3 arg3, type4 arg4) \
{ \
return (type) (INLINE_SYSCALL(name, 4, arg1, arg2, arg3, arg4)); \
}
#undef _syscall5
#define _syscall5(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4, \
type5,arg5) \
type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5) \
{ \
return (type) (INLINE_SYSCALL(name, 5, arg1, arg2, arg3, arg4, arg5)); \
}
#undef _syscall6
#define _syscall6(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4, \
type5,arg5,type6,arg6) \
type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5,type6 arg6) \
{ \
return (type) (INLINE_SYSCALL(name, 6, arg1, arg2, arg3, arg4, arg5, arg6)); \
}
/* Linux takes system call arguments in registers:
syscall number %d0 call-clobbered
arg 1 %d1 call-clobbered
arg 2 %d2 call-saved
arg 3 %d3 call-saved
arg 4 %d4 call-saved
arg 5 %d5 call-saved
The stack layout upon entering the function is:
20(%sp) Arg# 5
16(%sp) Arg# 4
12(%sp) Arg# 3
8(%sp) Arg# 2
4(%sp) Arg# 1
(%sp) Return address
(Of course a function with say 3 arguments does not have entries for
arguments 4 and 5.)
Separate move's are faster than movem, but need more space. Since
speed is more important, we don't use movem. Since %a0 and %a1 are
scratch registers, we can use them for saving as well. */
#undef INLINE_SYSCALL
#define INLINE_SYSCALL(name, nr, args...) \
({ unsigned int _sys_result = INTERNAL_SYSCALL (name, , nr, args); \
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_sys_result, ), 0))\
{ \
__set_errno (INTERNAL_SYSCALL_ERRNO (_sys_result, )); \
_sys_result = (unsigned int) -1; \
} \
(int) _sys_result; })
#undef INTERNAL_SYSCALL
#define INTERNAL_SYSCALL(name, err, nr, args...) \
({ unsigned int _sys_result; \
{ \
/* Load argument values in temporary variables
to perform side effects like function calls
before the call used registers are set. */ \
LOAD_ARGS_##nr (args) \
LOAD_REGS_##nr \
register int _d0 asm ("%d0") = __NR_##name; \
asm volatile ("trap #0" \
: "=d" (_d0) \
: "0" (_d0) ASM_ARGS_##nr \
: "memory"); \
_sys_result = _d0; \
} \
(int) _sys_result; })
#undef INTERNAL_SYSCALL_ERROR_P
#define INTERNAL_SYSCALL_ERROR_P(val, err) \
((unsigned int) (val) >= -4095U)
#undef INTERNAL_SYSCALL_ERRNO
#define INTERNAL_SYSCALL_ERRNO(val, err) (-(val))
#define LOAD_ARGS_0()
#define LOAD_REGS_0
#define ASM_ARGS_0
#define LOAD_ARGS_1(a1) \
LOAD_ARGS_0 () \
int __arg1 = (int) (a1);
#define LOAD_REGS_1 \
register int _d1 asm ("d1") = __arg1; \
LOAD_REGS_0
#define ASM_ARGS_1 ASM_ARGS_0, "d" (_d1)
#define LOAD_ARGS_2(a1, a2) \
LOAD_ARGS_1 (a1) \
int __arg2 = (int) (a2);
#define LOAD_REGS_2 \
register int _d2 asm ("d2") = __arg2; \
LOAD_REGS_1
#define ASM_ARGS_2 ASM_ARGS_1, "d" (_d2)
#define LOAD_ARGS_3(a1, a2, a3) \
LOAD_ARGS_2 (a1, a2) \
int __arg3 = (int) (a3);
#define LOAD_REGS_3 \
register int _d3 asm ("d3") = __arg3; \
LOAD_REGS_2
#define ASM_ARGS_3 ASM_ARGS_2, "d" (_d3)
#define LOAD_ARGS_4(a1, a2, a3, a4) \
LOAD_ARGS_3 (a1, a2, a3) \
int __arg4 = (int) (a4);
#define LOAD_REGS_4 \
register int _d4 asm ("d4") = __arg4; \
LOAD_REGS_3
#define ASM_ARGS_4 ASM_ARGS_3, "d" (_d4)
#define LOAD_ARGS_5(a1, a2, a3, a4, a5) \
LOAD_ARGS_4 (a1, a2, a3, a4) \
int __arg5 = (int) (a5);
#define LOAD_REGS_5 \
register int _d5 asm ("d5") = __arg5; \
LOAD_REGS_4
#define ASM_ARGS_5 ASM_ARGS_4, "d" (_d5)
#define LOAD_ARGS_6(a1, a2, a3, a4, a5, a6) \
LOAD_ARGS_5 (a1, a2, a3, a4, a5) \
int __arg6 = (int) (a6);
#define LOAD_REGS_6 \
register int _a0 asm ("a0") = __arg6; \
LOAD_REGS_5
#define ASM_ARGS_6 ASM_ARGS_5, "a" (_a0)
#endif /* __ASSEMBLER__ */
#endif /* _BITS_SYSCALLS_H */
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