From: A Large Angry SCM <gitzilla@gmail.com>
Date: Fri, 20 Apr 2007 01:53:15 GMT
Subject: Re: [RFD PATCH] git-fetch--tool and "insanely" long actions
Message-ID: <46281D0B.7080802@gmail.com>
In-Reply-To: <20070420013411.26401.77137.julian@quantumfyre.co.uk>

Julian Phillips wrote:
> On Thu, 19 Apr 2007, A Large Angry SCM wrote:
> 
>> This fixes a problem my repository mirroring script has been having since
>> the git-fetch--tool was added to master in the middle of March. However,
>> it is not a proper fix since it causes actual errors from snprintf() to be
>> ignored. A proper fix is complicated by the lack of a consistent indicator
>> that the buffer is too small across snprintf() implementations.
> .
> .
> .
>>       if (sizeof(msg) <= len)
>> -             die("insanely long action");
>> +             msg[sizeof(msg)-1] = '\0';
> 
> Or you could just let the whole thing through?
> 
> diff --git a/builtin-fetch--tool.c b/builtin-fetch--tool.c
> index e9d6764..9b5ae9f 100644
> --- a/builtin-fetch--tool.c
> +++ b/builtin-fetch--tool.c
> @@ -36,21 +36,26 @@ static int update_ref(const char *action,
>  		      unsigned char *oldval)
>  {
>  	int len;
> -	char msg[1024];
> +	char buffer[1024];
> +	int ret = 0;
> +	char *msg = buffer;
>  	char *rla = getenv("GIT_REFLOG_ACTION");
>  	static struct ref_lock *lock;
>  
>  	if (!rla)
>  		rla = "(reflog update)";
> -	len = snprintf(msg, sizeof(msg), "%s: %s", rla, action);
> -	if (sizeof(msg) <= len)
> -		die("insanely long action");
> +	len = strlen(rla) + strlen(action) + 3;
> +	if (len > sizeof(buffer))
> +		msg = xmalloc(len);
> +	snprintf(msg, len, "%s: %s", rla, action);
>  	lock = lock_any_ref_for_update(refname, oldval);
>  	if (!lock)
> -		return 1;
> +		ret = 1;
>  	if (write_ref_sha1(lock, sha1, msg) < 0)
> -		return 1;
> -	return 0;
> +		ret = 1;
> +	if (msg != buffer)
> +		free(msg);
> +	return ret;
>  }
>  
>  static int update_local_ref(const char *name,


See the last sentence in my original message. Yours also ignores errors 
from snprintf().