mirror of
https://github.com/torvalds/linux.git
synced 2026-04-18 14:53:58 -04:00
2eb64b936d
The standard syscall() function or macro uses the libc return value convention. Errors returned from the kernel as negative values are stored in errno and -1 is returned. Users who want to avoid using errno don't have a way to call raw syscalls and check the returned error. Add a new macro _syscall() which works like the standard syscall() but passes through the return value from the kernel unchanged. The naming scheme and return values match the named _sys_foo() system call wrappers already part of nolibc. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Willy Tarreau <w@1wt.eu> Link: https://patch.msgid.link/20260405-nolibc-syscall-v1-3-e5b12bc63211@weissschuh.net
21 lines
760 B
C
21 lines
760 B
C
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
|
|
/*
|
|
* syscall() definition for NOLIBC
|
|
* Copyright (C) 2024 Thomas Weißschuh <linux@weissschuh.net>
|
|
*/
|
|
|
|
/* make sure to include all global symbols */
|
|
#include "../nolibc.h"
|
|
|
|
#ifndef _NOLIBC_SYS_SYSCALL_H
|
|
#define _NOLIBC_SYS_SYSCALL_H
|
|
|
|
#define ___nolibc_syscall_narg(_0, _1, _2, _3, _4, _5, _6, N, ...) N
|
|
#define __nolibc_syscall_narg(...) ___nolibc_syscall_narg(__VA_ARGS__, 6, 5, 4, 3, 2, 1, 0)
|
|
#define __nolibc_syscall(N, ...) __nolibc_syscall##N(__VA_ARGS__)
|
|
#define __nolibc_syscall_n(N, ...) __nolibc_syscall(N, __VA_ARGS__)
|
|
#define _syscall(...) __nolibc_syscall_n(__nolibc_syscall_narg(__VA_ARGS__), ##__VA_ARGS__)
|
|
#define syscall(...) __sysret(_syscall(__VA_ARGS__))
|
|
|
|
#endif /* _NOLIBC_SYS_SYSCALL_H */
|