Re: [PATCH/RFC v2 2/3] make USE_NSEC work as expected

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 20, 2009, 08:35 UTC
Message-ID: <7vab8hfqug.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <24cefa55a62e2c898f9bd75ff7a6fe8e70836cf0.1235071656.git.barvik@broadpark.no>

Kjetil Barvik <barvik@broadpark.no> writes:

Show 19 quoted lines

> diff --git a/read-cache.c b/read-cache.c
> index 940ec76..ca4bec2 100644
> --- a/read-cache.c
> +++ b/read-cache.c
> @@ -67,8 +67,15 @@ void rename_index_entry_at(struct index_state *istate, int nr, const char *new_n
>   */
>  void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
>  {
> -	ce->ce_ctime = st->st_ctime;
> -	ce->ce_mtime = st->st_mtime;
> +	ce->ce_ctime.sec = (unsigned int)st->st_ctime;
> +	ce->ce_mtime.sec = (unsigned int)st->st_mtime;
> +#ifdef USE_NSEC
> +	ce->ce_ctime.nsec = (unsigned int)st->st_ctim.tv_nsec;
> +	ce->ce_mtime.nsec = (unsigned int)st->st_mtim.tv_nsec;
> +#else
> +	ce->ce_ctime.nsec = 0;
> +	ce->ce_mtime.nsec = 0;
> +#endif

How does this affect a use case where the same index file used with two instances of git (one compiled with and another without USE_NSEC)?

Show 9 quoted lines

> @@ -232,8 +246,16 @@ static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
>  static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce)
>  {
>  	return (!S_ISGITLINK(ce->ce_mode) &&
> -		istate->timestamp &&
> -		((unsigned int)istate->timestamp) <= ce->ce_mtime);
> +		istate->timestamp.sec &&
> +#ifdef USE_NSEC
> +		 /* nanosecond timestamped files can also be racy! */

Amusing ;-)

Show 16 quoted lines

> diff --git a/unpack-trees.c b/unpack-trees.c
> index e547282..44714cc 100644
> --- a/unpack-trees.c
> +++ b/unpack-trees.c
> @@ -380,8 +380,12 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
>  
>  	memset(&o->result, 0, sizeof(o->result));
>  	o->result.initialized = 1;
> -	if (o->src_index)
> -		o->result.timestamp = o->src_index->timestamp;
> +	if (o->src_index) {
> +		o->result.timestamp.sec = o->src_index->timestamp.sec;
> +#ifdef USE_NSEC
> +		o->result.timestamp.nsec = o->src_index->timestamp.nsec;
> +#endif
> +	}

Do we need this hunk?