This patch adds a new function valid_signal() that tests if its argument is
a valid signal number.
The reasons for adding this new function are:
- some code currently testing _NSIG directly has off-by-one errors.
Using this function instead avoids such errors.
- some code currently tests unsigned signal numbers for <0 which is
pointless and generates warnings when building with gcc -W. Using this
function instead avoids such warnings.
I considered various places to add this function but eventually settled on
include/linux/signal.h as the most logical place for it. If there's some
reason this is a bad choice then please let me know (hints as to a better
location are then welcome of course).
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>