Re: [PATCH 1/5] strbuf API additions and enhancements.

> Pierre Habouzit wrote:
>> +void strbuf_addvf(struct strbuf *sb, const char *fmt, va_list ap)
>> +{
>> +	int len;
>> +
>> +	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
>> +	if (len < 0) {
>> +		len = 0;
>> +	}
>> +	if (len > strbuf_avail(sb)) {
>> +		strbuf_grow(sb, len);
>> +		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
>> +		if (len > strbuf_avail(sb)) {
>> +			die("this should not happen, your snprintf is broken");
>> +		}
>> +	}
>> +	strbuf_setlen(sb, sb->len + len);
>> +}
> 
> The second vsnprintf won't work as the first one consumed all args
> from va_list ap.  You need to va_copy the ap.