Most of the library routines share the same syscall return logic:
In general, a 0 return value indicates success. A -1 return value indicates an error, and an error number is stored in errno. [1]
Let's add a __sysret() helper for the above logic to simplify the coding and shrink the code lines too.
Thomas suggested to use inline function instead of macro for __sysret().
Willy suggested to make __sysret() be always inline.
[1]: https://man7.org/linux/man-pages/man2/syscall.2.html
Suggested-by: Willy Tarreau w@1wt.eu Link: https://lore.kernel.org/linux-riscv/ZH1+hkhiA2+ItSvX@1wt.eu/ Suggested-by: Thomas Weißschuh linux@weissschuh.net Link: https://lore.kernel.org/linux-riscv/ea4e7442-7223-4211-ba29-70821e907888@t-8... Reviewed-by: Thomas Weißschuh linux@weissschuh.net Signed-off-by: Zhangjin Wu falcon@tinylab.org --- tools/include/nolibc/sys.h | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index 856249a11890..150777207468 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -28,6 +28,16 @@ #include "errno.h" #include "types.h"
+/* Syscall return helper, set errno as -ret when ret < 0 */ +static __inline__ __attribute__((unused, always_inline)) +long __sysret(long ret) +{ + if (ret < 0) { + SET_ERRNO(-ret); + ret = -1; + } + return ret; +}
/* Functions in this file only describe syscalls. They're declared static so * that the compiler usually decides to inline them while still being allowed