Re: [PATCH v5 05/15] pkt-line: add packet_write_gently_fmt()

From: Lars Schneider <larsxschneider@gmail.com>
Date: Aug 10, 2016, 14:10 UTC
Message-ID: <E6D0E830-764D-42E5-9F69-340F718B98B2@gmail.com>
In-Reply-To: <20160810134346.6nmf2sudwh56nq76@sigill.intra.peff.net>

Show 23 quoted lines

> On 10 Aug 2016, at 15:43, Jeff King <peff@peff.net> wrote:
> 
> On Wed, Aug 10, 2016 at 03:04:01PM +0200, larsxschneider@gmail.com wrote:
> 
>> +int packet_write_gently_fmt(int fd, const char *fmt, ...)
>> +{
>> +	static struct strbuf buf = STRBUF_INIT;
>> +	va_list args;
>> +
>> +	strbuf_reset(&buf);
>> +	va_start(args, fmt);
>> +	format_packet(1, &buf, fmt, args);
>> +	va_end(args);
>> +	packet_trace(buf.buf + 4, buf.len - 4, 1);
>> +	return (write_in_full(fd, buf.buf, buf.len) == buf.len ? 0 : -1);
>> +}
> 
> Could the end of this function just be:
> 
>  return packet_write_gently(fd, buf.buf, buf.len);
> 
> ? I guess we'd prefer to avoid that, because it incurs an extra
> memmove() of the data.

I don't think the memmove would be that expensive. However, format_packet() already creates the packet_header and packet_write_gently would do the same again, no?

> Similarly, I'd think this could share code with the non-gentle form
> (which should be able to just call this and die() if returns an error).
> Though sometimes the va_list transformation makes that awkward.

Yeah, the code duplication annoyed me, too. va_list was the reason I did it that way. Do you think that is something that needs to be addressed in the series?

Thanks, Lars