Re: [PATCH v4 2/4] path: optimize common dir checking

[David Turner <dturner@twopensource.com>]

On Fri, 2015-08-28 at 09:39 -0700, Junio C Hamano wrote:
> David Turner <dturner@twopensource.com> writes:
> 
> > On Wed, 2015-08-26 at 18:10 -0400, David Turner wrote:
> >> On Wed, 2015-08-26 at 14:15 -0700, Junio C Hamano wrote:
> >> > > + * For example, consider the following set of strings:
> >> > > + * abc
> >> > > + * def
> >> > > + * definite
> >> > > + * definition
> >> > > + *
> >> > > + * The trie would look look like:
> >> > > + * root: len = 0, value = (something), children a and d non-NULL.
> >> > 
> >> > "value = NULL", as there is no empty string registered in the trie?
> >> 
> >> Indeed.
> >> 
> >> > > + *    a: len = 2, contents = bc
> >> > 
> >> > "value = NULL" here, too (just showing I am following along, not
> >> > just skimming)?
> >> 
> >> Yep.
> >
> > No, wait. value should be non-NULL, since abc is in the string set. 
> 
> True.  Here is what I came up with on top of your original.  
> 
> 
> 
>  path.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/path.c b/path.c
> index 4100ba6..ce0530b 100644
> --- a/path.c
> +++ b/path.c
> @@ -133,12 +133,13 @@ struct common_dir common_list[] = {
>   * definition
>   *
>   * The trie would look look like:
> - * root: len = 0, value = (something), children a and d non-NULL.
> - *    a: len = 2, contents = bc
> - *    d: len = 2, contents = ef, children i non-NULL, value = (something)
> + * root: len = 0, children a and d non-NULL, value = NULL.
> + *    a: len = 2, contents = bc, value = (data for "abc")
> + *    d: len = 2, contents = ef, children i non-NULL, value = (data for "def")
>   *       i: len = 3, contents = nit, children e and i non-NULL, value = NULL
> - *           e: len = 0, children all NULL, value = (something)
> - *           i: len = 2, contents = on, children all NULL, value = (something)
> + *           e: len = 0, children all NULL, value = (data for "definite")
> + *           i: len = 2, contents = on, children all NULL,
> + *              value = (data for "definition")
>   */
>  struct trie {
>  	struct trie *children[256];

LGTM.