From: Erik Faye-Lund <kusmabite@gmail.com>
Date: Wed, 13 Jul 2011 22:29:11 GMT
Subject: Re: [PATCH] Do not log unless all connect() attempts fail
Message-ID: <CABPQNSazGsgqcZZ=q9VJ+2u=O32ePeRAjqo4+FuyVwCkX4y4nQ@mail.gmail.com>
In-Reply-To: <20110713210636.GF31965@sigill.intra.peff.net>

On Wed, Jul 13, 2011 at 11:06 PM, Jeff King <peff@peff.net> wrote:
> On Wed, Jul 13, 2011 at 11:23:33AM +0200, Erik Faye-Lund wrote:
>
>> >  static int git_tcp_connect_sock(char *host, int flags)
>> >  {
>> > +       struct strbuf error_message = STRBUF_INIT;
>> >        int sockfd = -1, saved_errno = 0;
>> >        const char *port = STR(DEFAULT_GIT_PORT);
>> >        struct addrinfo hints, *ai0, *ai;
>> > @@ -225,11 +226,8 @@ static int git_tcp_connect_sock(char *host, int flags)
>> >                }
>> >                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
>> >                        saved_errno = errno;
>> > -                       fprintf(stderr, "%s[%d: %s]: errno=%s\n",
>> > -                               host,
>> > -                               cnt,
>> > -                               ai_name(ai),
>> > -                               strerror(saved_errno));
>> > +                       strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
>> > +                               host, cnt, ai_name(ai), strerror(saved_errno));
>> >                        close(sockfd);
>> >                        sockfd = -1;
>> >                        continue;
>> > @@ -242,11 +240,13 @@ static int git_tcp_connect_sock(char *host, int flags)
>> >        freeaddrinfo(ai0);
>> >
>> >        if (sockfd < 0)
>> > -               die("unable to connect a socket (%s)", strerror(saved_errno));
>> > +               die("unable to connect to %s:\n%s", host, error_message.buf);
>> >
>>
>> This kills the output from the case where "sockfd < 0" evaluates to
>> true for the last entry in ai, no (just above your second hunk), no?
>> In that case errno gets copied to saved_errno, and the old output
>> would do strerror(old_errno), but now you just print the log you've
>> gathered, and don't even look at saved_errno.
>
> But that's OK, because the value of that saved_errno is in the gathered
> log, isn't it?

No, it's not. In the case where socket fails, we assign errno to
saved_errno and _continue_. So nothing gets logged about the error. If
there's only one entry in the address list, we don't end up reporting
anything; the strbuf is empty. We used to at least report
strerror(errno) in that case.