From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Sunshine <sunshine@sunshineco.com>
Subject: Re: [RFC/WIP PATCH 06/11] remote.h: add get_remote_capabilities, request_capabilities
Date: Wed, 27 May 2015 13:19:39 -0400
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To: Jeff King <peff@peff.net>
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On Wed, May 27, 2015 at 2:50 AM, Jeff King <peff@peff.net> wrote:
> On Tue, May 26, 2015 at 11:25:05PM -0400, Eric Sunshine wrote:
>
>> > +               len = packet_read(in, &src_buf, &src_len,
>> > +                                 packet_buffer, sizeof(packet_buffer),
>> > +                                 PACKET_READ_GENTLE_ON_EOF |
>> > +                                 PACKET_READ_CHOMP_NEWLINE);
>> > +               if (len < 0)
>> > +                       die_initial_contact(0);
>> > +
>> > +               if (!len)
>> > +                       break;
>> > +
>> > +               if (len > 4 && skip_prefix(line, "ERR ", &arg))
>>
>> The 'len > 4' check is needed because there's no guarantee that 'line'
>> is NUL-terminated. Correct?
>
> I think this was just blindly copied from get_remote_heads(). And I
> think that code was being overly paranoid. Ever since f3a3214 (Make
> send/receive-pack be closer to doing something interesting, 2005-06-29),
> the pkt-line reader will add an extra NUL to the buffer to ease cases
> like this.

Thanks. I had started digging into packet_read() to determine whether
it guaranteed NUL-termination, but didn't get far enough to decide. I
agree that if NUL-termination is guaranteed, then the 'len > 4' check
is superfluous (and confusing, which is why it caught my attention in
the first place).