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musl/include/sys/syscall.h

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overhaul syscall interface this commit shuffles around the location of syscall definitions so that we can make a syscall() library function with both SYS_* and __NR_* style syscall names available to user applications, provides the syscall() library function, and optimizes the code that performs the actual inline syscalls in the library itself. previously on i386 when built as PIC (shared library), syscalls were incurring bus lock (lock prefix) overhead at entry and exit, due to the way the ebx register was being loaded (xchg instruction with a memory operand). now the xchg takes place between two registers. further cleanup to arch/$(ARCH)/syscall.h is planned.
2011-03-19 22:51:42 +00:00
#ifndef _SYS_SYSCALL_H
#define _SYS_SYSCALL_H
#ifdef __cplusplus
extern "C" {
#endif
avoid "inline" in public headers for strict c89 compatibility while musl itself requires a c99 compiler, some applications insist on being compiled with c89 compilers, and use of "inline" in the headers was breaking them. much of this had been avoided already by just skipping the inline keyword in pre-c99 compilers or modes, but this new unified solution is cleaner and may/should result in better code generation in the default gcc configuration.
2012-09-02 16:46:06 +00:00
#if __STDC_VERSION__ >= 199901L || defined(__cplusplus)
#define __inline inline
#endif
cleanup various minor issues reported by nsz the changes to syscall_ret are mostly no-ops in the generated code, just cleanup of type issues and removal of some implementation-defined behavior. the one exception is the change in the comparison value, which is fixed so that 0xf...f000 (which in principle could be a valid return value for mmap, although probably never in reality) is not treated as an error return.
2011-09-26 04:59:28 +00:00
long __syscall_ret(unsigned long);
syscall overhaul part two - unify public and internal syscall interface with this patch, the syscallN() functions are no longer needed; a variadic syscall() macro allows syscalls with anywhere from 0 to 6 arguments to be made with a single macro name. also, manually casting each non-integer argument with (long) is no longer necessary; the casts are hidden in the macros. some source files which depended on being able to define the old macro SYSCALL_RETURNS_ERRNO have been modified to directly use __syscall() instead of syscall(). references to SYSCALL_SIGSET_SIZE and SYSCALL_LL have also been changed. x86_64 has not been tested, and may need a follow-up commit to fix any minor bugs/oversights.
2011-03-20 01:36:10 +00:00
long __syscall(long, ...);
long syscall(long, ...);
overhaul syscall interface this commit shuffles around the location of syscall definitions so that we can make a syscall() library function with both SYS_* and __NR_* style syscall names available to user applications, provides the syscall() library function, and optimizes the code that performs the actual inline syscalls in the library itself. previously on i386 when built as PIC (shared library), syscalls were incurring bus lock (lock prefix) overhead at entry and exit, due to the way the ebx register was being loaded (xchg instruction with a memory operand). now the xchg takes place between two registers. further cleanup to arch/$(ARCH)/syscall.h is planned.
2011-03-19 22:51:42 +00:00
#include <bits/syscall.h>
syscall overhaul part two - unify public and internal syscall interface with this patch, the syscallN() functions are no longer needed; a variadic syscall() macro allows syscalls with anywhere from 0 to 6 arguments to be made with a single macro name. also, manually casting each non-integer argument with (long) is no longer necessary; the casts are hidden in the macros. some source files which depended on being able to define the old macro SYSCALL_RETURNS_ERRNO have been modified to directly use __syscall() instead of syscall(). references to SYSCALL_SIGSET_SIZE and SYSCALL_LL have also been changed. x86_64 has not been tested, and may need a follow-up commit to fix any minor bugs/oversights.
2011-03-20 01:36:10 +00:00
#define __syscall1(n,a) __syscall1(n,(long)(a))
#define __syscall2(n,a,b) __syscall2(n,(long)(a),(long)(b))
#define __syscall3(n,a,b,c) __syscall3(n,(long)(a),(long)(b),(long)(c))
#define __syscall4(n,a,b,c,d) __syscall4(n,(long)(a),(long)(b),(long)(c),(long)(d))
#define __syscall5(n,a,b,c,d,e) __syscall5(n,(long)(a),(long)(b),(long)(c),(long)(d),(long)(e))
#define __syscall6(n,a,b,c,d,e,f) __syscall6(n,(long)(a),(long)(b),(long)(c),(long)(d),(long)(e),(long)(f))
#define __SYSCALL_NARGS_X(a,b,c,d,e,f,g,n,...) n
#define __SYSCALL_NARGS(...) __SYSCALL_NARGS_X(__VA_ARGS__,6,5,4,3,2,1,0)
#define __SYSCALL_CONCAT_X(a,b) a##b
#define __SYSCALL_CONCAT(a,b) __SYSCALL_CONCAT_X(a,b)
#define __SYSCALL_DISP(b,...) __SYSCALL_CONCAT(b,__SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
overhaul syscall interface this commit shuffles around the location of syscall definitions so that we can make a syscall() library function with both SYS_* and __NR_* style syscall names available to user applications, provides the syscall() library function, and optimizes the code that performs the actual inline syscalls in the library itself. previously on i386 when built as PIC (shared library), syscalls were incurring bus lock (lock prefix) overhead at entry and exit, due to the way the ebx register was being loaded (xchg instruction with a memory operand). now the xchg takes place between two registers. further cleanup to arch/$(ARCH)/syscall.h is planned.
2011-03-19 22:51:42 +00:00
syscall overhaul part two - unify public and internal syscall interface with this patch, the syscallN() functions are no longer needed; a variadic syscall() macro allows syscalls with anywhere from 0 to 6 arguments to be made with a single macro name. also, manually casting each non-integer argument with (long) is no longer necessary; the casts are hidden in the macros. some source files which depended on being able to define the old macro SYSCALL_RETURNS_ERRNO have been modified to directly use __syscall() instead of syscall(). references to SYSCALL_SIGSET_SIZE and SYSCALL_LL have also been changed. x86_64 has not been tested, and may need a follow-up commit to fix any minor bugs/oversights.
2011-03-20 01:36:10 +00:00
#define __syscall(...) __SYSCALL_DISP(__syscall,__VA_ARGS__)
#define syscall(...) __syscall_ret(__syscall(__VA_ARGS__))
overhaul syscall interface this commit shuffles around the location of syscall definitions so that we can make a syscall() library function with both SYS_* and __NR_* style syscall names available to user applications, provides the syscall() library function, and optimizes the code that performs the actual inline syscalls in the library itself. previously on i386 when built as PIC (shared library), syscalls were incurring bus lock (lock prefix) overhead at entry and exit, due to the way the ebx register was being loaded (xchg instruction with a memory operand). now the xchg takes place between two registers. further cleanup to arch/$(ARCH)/syscall.h is planned.
2011-03-19 22:51:42 +00:00
#ifdef __cplusplus
}
#endif
#endif