Re: [Qemu-devel] [RFC] qed: Add QEMU Enhanced Disk format

[Luca Tettamanti <kronos.it@gmail.com>]

On Mon, Sep 6, 2010 at 12:25 PM, Alexander Graf <agraf@suse.de> wrote:
> On 06.09.2010, at 12:04, Stefan Hajnoczi wrote:
>> +
>> +const char *bytes_to_str(uint64_t size)
>> +{
>> +    static char buffer[64];
>> +
>> +    if (size < (1ULL << 10)) {
>> +        snprintf(buffer, sizeof(buffer), "%" PRIu64 " byte(s)", size);
>> +    } else if (size < (1ULL << 20)) {
>> +        snprintf(buffer, sizeof(buffer), "%" PRIu64 " KB(s)", size >> 10);
>> +    } else if (size < (1ULL << 30)) {
>> +        snprintf(buffer, sizeof(buffer), "%" PRIu64 " MB(s)", size >> 20);
>> +    } else if (size < (1ULL << 40)) {
>> +        snprintf(buffer, sizeof(buffer), "%" PRIu64 " GB(s)", size >> 30);
>> +    } else {
>> +        snprintf(buffer, sizeof(buffer), "%" PRIu64 " TB(s)", size >> 40);
>> +    }
>> +
>> +    return buffer;
>
> This returns a variable from the stack! Please make the target buffer caller defined.

It's static, so it's formally correct. But probably not a good idea :)

Luca