Re: [PATCH 06/21] convert manual allocations to argv_array

[Jeff King <peff@peff.net>]

On Sat, Feb 20, 2016 at 03:07:00AM -0500, Eric Sunshine wrote:

> > diff --git a/line-log.c b/line-log.c
> > @@ -746,23 +747,16 @@ void line_log_init(struct rev_info *rev, const char *prefix, struct string_list
> >         if (!rev->diffopt.detect_rename) {
> > -               int i, count = 0;
> > -               struct line_log_data *r = range;
> > -               const char **paths;
> > -               while (r) {
> > -                       count++;
> > -                       r = r->next;
> > -               }
> > -               paths = xmalloc((count+1)*sizeof(char *));
> > -               r = range;
> > -               for (i = 0; i < count; i++) {
> > -                       paths[i] = xstrdup(r->path);
> > -                       r = r->next;
> > -               }
> > -               paths[count] = NULL;
> > +               struct line_log_data *r;
> > +               struct argv_array paths = ARGV_ARRAY_INIT;
> > +
> > +               for (r = range; r; r = r->next)
> > +                       argv_array_push(&paths, r->path);
> >                 parse_pathspec(&rev->diffopt.pathspec, 0,
> > -                              PATHSPEC_PREFER_FULL, "", paths);
> > -               free(paths);
> > +                              PATHSPEC_PREFER_FULL, "", paths.argv);
> > +               /* argv strings are now owned by pathspec */
> > +               paths.argc = 0;
> > +               argv_array_clear(&paths);
> 
> This overly intimate knowledge of the internal implementation of
> argv_array_clear() is rather ugly.

Yep, I agree. Suggestions?

We can just leak the array of "char *". This function is called only
once per program invocation, and that's unlikely to change.

I guess we can make an argv_array_detach_strings() function. Or maybe
even just argv_array_detach() would be less gross, and then this
function could manually free the array but not the strings themselves.

-Peff