| Message ID | 20200904154547.3836-3-brgl@bgdev.pl |
|---|---|
| State | New |
| Headers | show |
| Series | gpio: mockup: support dynamically created and removed chips | expand |
On Fri, Sep 04, 2020 at 05:45:26PM +0200, Bartosz Golaszewski wrote: > From: Bartosz Golaszewski <bgolaszewski@baylibre.com> > > 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 <bgolaszewski@baylibre.com> > --- > include/linux/string_helpers.h | 2 ++ > lib/string_helpers.c | 22 ++++++++++++++++++++++ > 2 files changed, 24 insertions(+) > > diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h > index 86f150c2a6b6..55b25120a1c6 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 **str_array, size_t num_str); > + > #endif > diff --git a/lib/string_helpers.c b/lib/string_helpers.c > index 963050c0283e..22505efc6aae 100644 > --- a/lib/string_helpers.c > +++ b/lib/string_helpers.c > @@ -649,3 +649,25 @@ 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 > + * > + * @str_array: Dynamically allocated array of strings to free. If NULL - the > + * function does nothing. > + * @num_str: Number of strings (starting from the beginning of the array) to > + * free. > + */ > +void kfree_strarray(char **str_array, size_t num_str) > +{ > + unsigned int i; > + if (!str_array) > + return; Shouldn't we expect that caller will supply NULL, 0 and above check is not needed? > + for (i = 0; i < num_str; i++) > + kfree(str_array[i]); > + kfree(str_array); > +} > +EXPORT_SYMBOL_GPL(kfree_strarray); > -- > 2.26.1 >
diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index 86f150c2a6b6..55b25120a1c6 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 **str_array, size_t num_str); + #endif diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 963050c0283e..22505efc6aae 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -649,3 +649,25 @@ 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 + * + * @str_array: Dynamically allocated array of strings to free. If NULL - the + * function does nothing. + * @num_str: Number of strings (starting from the beginning of the array) to + * free. + */ +void kfree_strarray(char **str_array, size_t num_str) +{ + unsigned int i; + + if (!str_array) + return; + + for (i = 0; i < num_str; i++) + kfree(str_array[i]); + kfree(str_array); +} +EXPORT_SYMBOL_GPL(kfree_strarray);