From 0fd16012adc0a994a7ce980a78e22e4de6220778 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Tue, 29 Sep 2020 12:09:55 +0200 Subject: [PATCH] lib: string_helpers: provide kfree_strarray() There's a common pattern of dynamically allocating an array of char pointers and then also dynamically allocating each string in this array. Provide a helper for freeing such a string array with one call. Signed-off-by: Bartosz Golaszewski Reviewed-by: Andy Shevchenko --- include/linux/string_helpers.h | 2 ++ lib/string_helpers.c | 23 +++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index 86f150c2a6b6..fa06dcdc481e 100644 --- a/include/linux/string_helpers.h +++ b/include/linux/string_helpers.h @@ -94,4 +94,6 @@ char *kstrdup_quotable(const char *src, gfp_t gfp); char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp); char *kstrdup_quotable_file(struct file *file, gfp_t gfp); +void kfree_strarray(char **array, size_t n); + #endif diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 963050c0283e..7f2d5fbaf243 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -649,3 +649,26 @@ char *kstrdup_quotable_file(struct file *file, gfp_t gfp) return pathname; } EXPORT_SYMBOL_GPL(kstrdup_quotable_file); + +/** + * kfree_strarray - free a number of dynamically allocated strings contained + * in an array and the array itself + * + * @array: Dynamically allocated array of strings to free. + * @n: Number of strings (starting from the beginning of the array) to free. + * + * Passing a non-NULL @array and @n == 0 as well as NULL @array are valid + * use-cases. If @array is NULL, the function does nothing. + */ +void kfree_strarray(char **array, size_t n) +{ + unsigned int i; + + if (!array) + return; + + for (i = 0; i < n; i++) + kfree(array[i]); + kfree(array); +} +EXPORT_SYMBOL_GPL(kfree_strarray); -- 2.11.0