This helper is similar to __sysfs_match_string() with the exception that it ignores NULL elements within the array. It takes an extra parameter (called `gaps`) which when true will ignore the NULL elements. When false, this function behaves exactly like `__sysfs_match_string()`. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> --- include/linux/string.h | 2 ++ lib/string.c | 48 ++++++++++++++++++++++++++++++++---------- 2 files changed, 39 insertions(+), 11 deletions(-) diff --git a/include/linux/string.h b/include/linux/string.h index 7927b875f80c..08e4a33b5f29 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -190,6 +190,8 @@ static inline int strtobool(const char *s, bool *res) int match_string(const char * const *array, size_t n, const char *string); int __sysfs_match_string(const char * const *array, size_t n, const char *s); +int __sysfs_match_string_with_gaps(const char * const *array, size_t n, + const char *str); /** * sysfs_match_string - matches given string in an array diff --git a/lib/string.c b/lib/string.c index 38e4ca08e757..2ae3b7e5ff3d 100644 --- a/lib/string.c +++ b/lib/string.c @@ -658,32 +658,58 @@ int match_string(const char * const *array, size_t n, const char *string) } EXPORT_SYMBOL(match_string); -/** - * __sysfs_match_string - matches given string in an array - * @array: array of strings - * @n: number of strings in the array or -1 for NULL terminated arrays - * @str: string to match with - * - * Returns index of @str in the @array or -EINVAL, just like match_string(). - * Uses sysfs_streq instead of strcmp for matching. - */ -int __sysfs_match_string(const char * const *array, size_t n, const char *str) +static int __sysfs_match_string_common(const char * const *array, size_t n, + const char *str, bool gaps) { const char *item; int index; for (index = 0; index < n; index++) { item = array[index]; - if (!item) + if (!item) { + if (gaps) + continue; break; + } if (sysfs_streq(item, str)) return index; } return -EINVAL; } + +/** + * __sysfs_match_string - matches given string in an array + * @array: array of strings + * @n: number of strings in the array or -1 for NULL terminated arrays + * @str: string to match with + * + * Returns index of @str in the @array or -EINVAL, just like match_string(). + * Uses sysfs_streq instead of strcmp for matching. + */ +int __sysfs_match_string(const char * const *array, size_t n, const char *str) +{ + return __sysfs_match_string_common(array, n, str, false); +} EXPORT_SYMBOL(__sysfs_match_string); +/** + * __sysfs_match_string_with_gaps - matches string in array ignoring NULLs + * @array: array of strings + * @n: number of strings in the array or -1 for NULL terminated arrays + * @str: string to match with + * + * Returns index of @str in the @array or -EINVAL, just like match_string(). + * Uses sysfs_streq instead of strcmp for matching. + * Ignores NULL entries within the @array. + */ +int __sysfs_match_string_with_gaps(const char * const *array, size_t n, + const char *str) +{ + return __sysfs_match_string_common(array, n, str, true); +} +EXPORT_SYMBOL(__sysfs_match_string_with_gaps); + #ifndef __HAVE_ARCH_MEMSET /** * memset - Fill a region of memory with the given value -- 2.17.1