err.h: add helper function to simplify pointer error checking

There are quite a few instances in the kernel of checks of pointers both
against NULL and against the errno range, handling both cases identically.
This additional helper function would simplify such code.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Phil Carmody 2009-12-14 18:00:29 -08:00 committed by Linus Torvalds
parent 9385565e20
commit 603c4ba96b

View File

@ -34,6 +34,11 @@ static inline long IS_ERR(const void *ptr)
return IS_ERR_VALUE((unsigned long)ptr);
}
static inline long IS_ERR_OR_NULL(const void *ptr)
{
return !ptr || IS_ERR_VALUE((unsigned long)ptr);
}
/**
* ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
* @ptr: The pointer to cast.