On Wed, Jul 8, 2026 at 8:54 AM Samuel Moelius
<[email protected]> wrote:
>
> -static int parse_cblock_range(struct cache *cache, const char *str,
> +static int parse_cblock_range(struct cache *cache, char *str,
> struct cblock_range *result)
> {
> - char dummy;
> - uint64_t b, e;
> + char *begin = strsep(&str, "-");
> + unsigned int b, e;
> int r;
>
> - /*
> - * Try and parse form (ii) first.
> - */
> - r = sscanf(str, "%llu-%llu%c", &b, &e, &dummy);
> + if (str) {
> + r = kstrtouint(begin, 10, &b);
> + if (r)
> + goto bad;
> +
> + r = kstrtouint(str, 10, &e);
> + if (r)
> + goto bad;
>
> - if (r == 2) {
> result->begin = to_cblock(b);
> result->end = to_cblock(e);
> return 0;
> }
>
> - /*
> - * That didn't work, try form (i).
> - */
> - r = sscanf(str, "%llu%c", &b, &dummy);
> -
> - if (r == 1) {
> + r = kstrtouint(begin, 10, &b);
This duplicates the kstrtouint(begin) call below. I'd prefer parse
begin once, then branch on whether str is non-NULL.
> + if (!r) {
> result->begin = to_cblock(b);
> - result->end = to_cblock(from_cblock(result->begin) + 1u);
> + result->end = cblock_succ(result->begin);
> return 0;
> }
This should follow the same early-return-on-error pattern above: goto
bad on failure, and keep the happy path unindented.
> - DMERR("%s: invalid cblock range '%s'", cache_device_name(cache), str);
> +bad:
> + DMERR("%s: invalid cblock range '%s%s%s'", cache_device_name(cache),
> + begin, str ? "-" : "", str ?: "");
Since strsep() is destructive, printing the rejected token is simpler
and more useful for debugging. How about:
blocknr = strsep(&str)
r = strtouint(blocknr)
...
if (str) {
blocknr = str
r = strtouint(blocknr)
...
} else {
... // single-value case
}
DMERR("%s", blocknr)
