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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Andy Shevchenko 2021-11-05 14:42:24 +02:00
parent fa55b7dcdc
commit 418e0a3551
2 changed files with 34 additions and 0 deletions

View File

@ -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

View File

@ -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