tools/nolibc: sys.h: add a syscall return helper

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 <[email protected]>
Link: https://lore.kernel.org/linux-riscv/[email protected]/
Suggested-by: Thomas Weißschuh <[email protected]>
Link: https://lore.kernel.org/linux-riscv/[email protected]/
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
Signed-off-by: Willy Tarreau <[email protected]>

0 files changed, 0 insertions, 0 deletions