Commit 418e0a35 authored by Andy Shevchenko's avatar Andy Shevchenko
Browse files

lib/string_helpers: Introduce kasprintf_strarray() 



We have a few users already that basically want to have array of
sequential strings to be allocated and filled.

Provide a helper for them (basically adjusted version from gpio-mockup.c).

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent fa55b7dc

include/linux/string_helpers.h

+1 −0
Original line number Diff line number Diff line
@@ -100,6 +100,7 @@ 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);



char **kasprintf_strarray(gfp_t gfp, const char *prefix, size_t n);

void kfree_strarray(char **array, size_t n);



#endif

lib/string_helpers.c

+33 −0
Original line number Diff line number Diff line
@@ -674,6 +674,39 @@ char *kstrdup_quotable_file(struct file *file, gfp_t gfp) 
}

EXPORT_SYMBOL_GPL(kstrdup_quotable_file);



/**

 * kasprintf_strarray - allocate and fill array of sequential strings

 * @gfp: flags for the slab allocator

 * @prefix: prefix to be used

 * @n: amount of lines to be allocated and filled

 *

 * Allocates and fills @n strings using pattern "%s-%zu", where prefix

 * is provided by caller. The caller is responsible to free them with

 * kfree_strarray() after use.

 *

 * Returns array of strings or NULL when memory can't be allocated.

 */

char **kasprintf_strarray(gfp_t gfp, const char *prefix, size_t n)

{

	char **names;

	size_t i;



	names = kcalloc(n + 1, sizeof(char *), gfp);

	if (!names)

		return NULL;



	for (i = 0; i < n; i++) {

		names[i] = kasprintf(gfp, "%s-%zu", prefix, i);

		if (!names[i]) {

			kfree_strarray(names, i);

			return NULL;

		}

	}



	return names;

}

EXPORT_SYMBOL_GPL(kasprintf_strarray);



/**

 * kfree_strarray - free a number of dynamically allocated strings contained

 *                  in an array and the array itself