Re: [PATCH v2 05/27] upload-pack: factor out processing lines

[Derrick Stolee <stolee@xxxxxxxxx>]

On 1/26/2018 4:33 PM, Brandon Williams wrote:
> On 01/26, Stefan Beller wrote:
> > On Thu, Jan 25, 2018 at 3:58 PM, Brandon Williams <bmwill@xxxxxxxxxx> wrote:
> > > Factor out the logic for processing shallow, deepen, deepen_since, and
> > > deepen_not lines into their own functions to simplify the
> > > 'receive_needs()' function in addition to making it easier to reuse some
> > > of this logic when implementing protocol_v2.
> > >
> > > Signed-off-by: Brandon Williams <bmwill@xxxxxxxxxx>
> > > ---
> > >   upload-pack.c | 113 ++++++++++++++++++++++++++++++++++++++--------------------
> > >   1 file changed, 74 insertions(+), 39 deletions(-)
> > >
> > > diff --git a/upload-pack.c b/upload-pack.c
> > > index 2ad73a98b..42d83d5b1 100644
> > > --- a/upload-pack.c
> > > +++ b/upload-pack.c
> > > @@ -724,6 +724,75 @@ static void deepen_by_rev_list(int ac, const char **av,
> > >          packet_flush(1);
> > >   }
> > >
> > > +static int process_shallow(const char *line, struct object_array *shallows)
> > > +{
> > > +       const char *arg;
> > > +       if (skip_prefix(line, "shallow ", &arg)) {
> > stylistic nit:
> >
> >      You could invert the condition in each of the process_* functions
> >      to just have
> >
> >          if (!skip_prefix...))
> >              return 0
> >
> >          /* less indented code goes here */
> >
> >          return 1;
> >
> >      That way we have less indentation as well as easier code.
> >      (The reader doesn't need to keep in mind what the else
> >      part is about; it is a rather local decision to bail out instead
> >      of having the return at the end of the function.)
> I was trying to move the existing code into helper functions so
> rewriting them in transit may make it less reviewable?

I think the way you kept to the existing code as much as possible is 
good and easier to review. Perhaps a style pass after the patch lands is 
good for #leftoverbits.

> > > +               struct object_id oid;
> > > +               struct object *object;
> > > +               if (get_oid_hex(arg, &oid))
> > > +                       die("invalid shallow line: %s", line);
> > > +               object = parse_object(&oid);
> > > +               if (!object)
> > > +                       return 1;
> > > +               if (object->type != OBJ_COMMIT)
> > > +                       die("invalid shallow object %s", oid_to_hex(&oid));
> > > +               if (!(object->flags & CLIENT_SHALLOW)) {
> > > +                       object->flags |= CLIENT_SHALLOW;
> > > +                       add_object_array(object, NULL, shallows);
> > > +               }
> > > +               return 1;
> > > +       }
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int process_deepen(const char *line, int *depth)
> > > +{
> > > +       const char *arg;
> > > +       if (skip_prefix(line, "deepen ", &arg)) {
> > > +               char *end = NULL;
> > > +               *depth = (int) strtol(arg, &end, 0);

nit: space between (int) and strtol?

> > > +               if (!end || *end || *depth <= 0)
> > > +                       die("Invalid deepen: %s", line);
> > > +               return 1;
> > > +       }
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int process_deepen_since(const char *line, timestamp_t *deepen_since, int *deepen_rev_list)
> > > +{
> > > +       const char *arg;
> > > +       if (skip_prefix(line, "deepen-since ", &arg)) {
> > > +               char *end = NULL;
> > > +               *deepen_since = parse_timestamp(arg, &end, 0);
> > > +               if (!end || *end || !deepen_since ||
> > > +                   /* revisions.c's max_age -1 is special */
> > > +                   *deepen_since == -1)
> > > +                       die("Invalid deepen-since: %s", line);
> > > +               *deepen_rev_list = 1;
> > > +               return 1;
> > > +       }
> > > +       return 0;
> > > +}
> > > +
> > > +static int process_deepen_not(const char *line, struct string_list *deepen_not, int *deepen_rev_list)
> > > +{
> > > +       const char *arg;
> > > +       if (skip_prefix(line, "deepen-not ", &arg)) {
> > > +               char *ref = NULL;
> > > +               struct object_id oid;
> > > +               if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
> > > +                       die("git upload-pack: ambiguous deepen-not: %s", line);
> > > +               string_list_append(deepen_not, ref);
> > > +               free(ref);
> > > +               *deepen_rev_list = 1;
> > > +               return 1;
> > > +       }
> > > +       return 0;
> > > +}
> > > +
> > >   static void receive_needs(void)
> > >   {
> > >          struct object_array shallows = OBJECT_ARRAY_INIT;
> > > @@ -745,49 +814,15 @@ static void receive_needs(void)
> > >                  if (!line)
> > >                          break;
> > >
> > > -               if (skip_prefix(line, "shallow ", &arg)) {
> > > -                       struct object_id oid;
> > > -                       struct object *object;
> > > -                       if (get_oid_hex(arg, &oid))
> > > -                               die("invalid shallow line: %s", line);
> > > -                       object = parse_object(&oid);
> > > -                       if (!object)
> > > -                               continue;
> > > -                       if (object->type != OBJ_COMMIT)
> > > -                               die("invalid shallow object %s", oid_to_hex(&oid));
> > > -                       if (!(object->flags & CLIENT_SHALLOW)) {
> > > -                               object->flags |= CLIENT_SHALLOW;
> > > -                               add_object_array(object, NULL, &shallows);
> > > -                       }
> > > +               if (process_shallow(line, &shallows))
> > >                          continue;
> > > -               }
> > > -               if (skip_prefix(line, "deepen ", &arg)) {
> > > -                       char *end = NULL;
> > > -                       depth = strtol(arg, &end, 0);
> > > -                       if (!end || *end || depth <= 0)
> > > -                               die("Invalid deepen: %s", line);
> > > +               if (process_deepen(line, &depth))
> > >                          continue;
> > > -               }
> > > -               if (skip_prefix(line, "deepen-since ", &arg)) {
> > > -                       char *end = NULL;
> > > -                       deepen_since = parse_timestamp(arg, &end, 0);
> > > -                       if (!end || *end || !deepen_since ||
> > > -                           /* revisions.c's max_age -1 is special */
> > > -                           deepen_since == -1)
> > > -                               die("Invalid deepen-since: %s", line);
> > > -                       deepen_rev_list = 1;
> > > +               if (process_deepen_since(line, &deepen_since, &deepen_rev_list))
> > >                          continue;
> > > -               }
> > > -               if (skip_prefix(line, "deepen-not ", &arg)) {
> > > -                       char *ref = NULL;
> > > -                       struct object_id oid;
> > > -                       if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
> > > -                               die("git upload-pack: ambiguous deepen-not: %s", line);
> > > -                       string_list_append(&deepen_not, ref);
> > > -                       free(ref);
> > > -                       deepen_rev_list = 1;
> > > +               if (process_deepen_not(line, &deepen_not, &deepen_rev_list))
> > >                          continue;
> > > -               }
> > > +
> > >                  if (!skip_prefix(line, "want ", &arg) ||
> > >                      get_oid_hex(arg, &oid_buf))
> > >                          die("git upload-pack: protocol error, "
> > > --
> > > 2.16.0.rc1.238.g530d649a79-goog