On Thu, May 29, 2014 at 09:42:11AM +0800, Qu Wenruo wrote:
> When using parse_size(), even non-numeric value is passed, it will only
> give error message "ERROR: size value is empty", which is quite
> confusing for end users.
>
> This patch will introduce more meaningful error message for the
> following new cases
> 1) Invalid size string (non-numeric string)
> 2) Minus size value (like "-1K")
>
> Also this patch will take full use of endptr returned by strtoll() to
> reduce unneeded loop.
>
> Signed-off-by: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx>
> ---
> utils.c | 56 +++++++++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 39 insertions(+), 17 deletions(-)
>
> diff --git a/utils.c b/utils.c
> index 392c5cf..499f08f 100644
> --- a/utils.c
> +++ b/utils.c
> @@ -1612,18 +1612,45 @@ scan_again:
>
> u64 parse_size(char *s)
> {
> - int i;
> char c;
> + char *endptr;
> u64 mult = 1;
> + long long int signed_ret;
> + u64 ret;
>
> - for (i = 0; s && s[i] && isdigit(s[i]); i++) ;
> - if (!i) {
> - fprintf(stderr, "ERROR: size value is empty\n");
> - exit(50);
> + if (!s) {
> + fprintf(stderr, "ERROR: Size value is empty\n");
> + exit(1);
We never pass a NULL pointer to parse_size so this check will be always
false. Previously it verified that there are at least some digits.
> }
> -
> - if (s[i]) {
> - c = tolower(s[i]);
> + signed_ret = strtoll(s, &endptr, 10);
> + if (endptr == s) {
> + fprintf(stderr, "ERROR: Size value '%s' is invalid\n", s);
> + exit(1);
> + }
> + if (endptr[0] && endptr[1]) {
> + fprintf(stderr, "ERROR: Illegal suffix contains character '%c' in wrong position\n",
> + endptr[1]);
> + exit(1);
> + }
> + if (signed_ret <= 0) {
> + fprintf(stderr,
> + "ERROR: Size value '%s' is less equal than 0\n", s);
> + exit(1);
> + }
> + /* strtoll returns LLONG_MAX when overflow, if this happens,
> + * need to call strtoull to get the real size */
> + if (errno == ERANGE && signed_ret == LLONG_MAX) {
> + ret = strtoull(s, NULL, 10);
Why do you parse the number twice? Negative sizes are currently not used
so you can reject them.
> + if (errno == ERANGE && ret == ULLONG_MAX) {
> + fprintf(stderr,
> + "ERROR: Size value '%s' is too large for u64\n",
> + s);
> + exit(1);
> + }
> + } else
> + ret = signed_ret;
> + if (endptr[0]) {
> + c = tolower(endptr[0]);
> switch (c) {
> case 'e':
> mult *= 1024;
> @@ -1646,18 +1673,13 @@ u64 parse_size(char *s)
> case 'b':
> break;
> default:
> - fprintf(stderr, "ERROR: Unknown size descriptor "
> - "'%c'\n", c);
> + fprintf(stderr, "ERROR: Unknown size descriptor '%c'\n", c);
> exit(1);
> }
> }
> - if (s[i] && s[i+1]) {
> - fprintf(stderr, "ERROR: Illegal suffix contains "
> - "character '%c' in wrong position\n",
> - s[i+1]);
> - exit(51);
> - }
> - return strtoull(s, NULL, 10) * mult;
> +
> + ret *= mult;
Although there was no overflow check before, I think it should be here.
Eg. 12345678P is a valid size string but the result does not fit u64.
> + return ret;
> }
--
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