Functions like devm_kzalloc, kmalloc_array, devm_ioremap,
usb_alloc_urb, alloc_netdev return NULL as a return value on failure.
Generally, When NULL represents failure, !x is commonly used.
This patch cleans up the tests on the results of these functions, thereby
using !x instead of x == NULL or NULL == x. This is done via following
coccinelle script:
@prob_7@
identifier x;
statement S;
@@
(
x = devm_kzalloc(...);
|
x = usb_alloc_urb(...);
|
x = kmalloc_array(...);
|
x = devm_ioremap(...);
|
x = alloc_netdev(...);
)
...
- if(NULL == x)
+ if(!x)
S
Further we have used isomorphism characteristics of coccinelle to
indicate x == NULL and NULL == x are equivalent. This is done via
following iso script.
Expression
@ is_null @ expression X; @@
X == NULL <=> NULL == X
Signed-off-by: Somya Anand <somyaanand214@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
87e3dbc27c