On Tue, Jun 25, 2019 at 04:01:04PM +0300, Alexandru Ardelean wrote: > The documentation the `__sysfs_match_string()` helper mentions that `n` > (the size of the given array) should be: > * @n: number of strings in the array or -1 for NULL terminated arrays > > The behavior of the function is different, in the sense that it exits on > the first NULL element in the array. > > This patch changes the behavior, to exit the loop when a NULL element is > found, and the size of the array is provided as -1. > > All current users of __sysfs_match_string() & sysfs_match_string() provide > contiguous arrays of strings, so this behavior change doesn't influence > anything (at this point in time). > > This behavior change allows for an array of strings to have NULL elements > within the array, which will be ignored. This is particularly useful when > creating mapping of strings and integers (as bitfields or other HW > description).
Since it does nothing for current users and comes without an example, it's hard to justify the need. The code itself looks good to me. > > Signed-off-by: Alexandru Ardelean <[email protected]> > --- > > Changelog v3 -> v4: > * split this patch away from series; there are some unsolved discussions > that will probably need resolving per sub-system > > lib/string.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/lib/string.c b/lib/string.c > index 3ab861c1a857..5bea3f98478a 100644 > --- a/lib/string.c > +++ b/lib/string.c > @@ -674,8 +674,11 @@ int __sysfs_match_string(const char * const *array, > size_t n, const char *str) > > for (index = 0; index < n; index++) { > item = array[index]; > - if (!item) > + if (!item) { > + if (n != (size_t)-1) > + continue; > break; > + } > if (sysfs_streq(item, str)) > return index; > } > -- > 2.20.1 > -- With Best Regards, Andy Shevchenko
