libbb: use BUILD_BUG_ON in utoa_to_buf()

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-03-28 17:12:56 +02:00
parent 123fdda0a4
commit e4defe826b

View File

@ -59,24 +59,23 @@ char* FAST_FUNC strncpy_IFNAMSIZ(char *dst, const char *src)
* A truncated result contains the first few digits of the result ala strncpy.
* Returns a pointer past last generated digit, does _not_ store NUL.
*/
void BUG_sizeof(void);
char* FAST_FUNC utoa_to_buf(unsigned n, char *buf, unsigned buflen)
{
unsigned i, out, res;
if (buflen) {
out = 0;
BUILD_BUG_ON(sizeof(n) != 4 && sizeof(n) != 8);
if (sizeof(n) == 4)
// 2^32-1 = 4294967295
i = 1000000000;
#if UINT_MAX > 4294967295 /* prevents warning about "const too large" */
#if UINT_MAX > 0xffffffff /* prevents warning about "const too large" */
else
if (sizeof(n) == 8)
// 2^64-1 = 18446744073709551615
i = 10000000000000000000;
#endif
else
BUG_sizeof();
for (; i; i /= 10) {
res = n / i;
n = n % i;