From 428905da6ec4a02d08dfcc09013035594f666a31 Mon Sep 17 00:00:00 2001 From: Zhangjin Wu Date: Wed, 28 Jun 2023 21:08:32 +0800 Subject: [PATCH] tools/nolibc: sys.h: add a syscall return helper MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Link: https://lore.kernel.org/linux-riscv/ZH1+hkhiA2+ItSvX@1wt.eu/ Suggested-by: Thomas Weißschuh Link: https://lore.kernel.org/linux-riscv/ea4e7442-7223-4211-ba29-70821e907888@t-8ch.de/ Reviewed-by: Thomas Weißschuh Signed-off-by: Zhangjin Wu Signed-off-by: Willy Tarreau --- 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 5464f93..097eef8 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 -- 2.7.4