Re: [PATCH v3 1/9] ref-filter: add option to align atoms to the left

> On Mon, Jul 20, 2015 at 1:22 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> Add a new atom "align" and support %(align:X) where X is a number.
>> This will align the preceeding atom value to the left followed by
>> spaces for a total length of X characters. If X is less than the item
>> size, the entire atom value is printed.
>>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>> diff --git a/ref-filter.c b/ref-filter.c
>> index 7561727..93f59aa 100644
>> --- a/ref-filter.c
>> +++ b/ref-filter.c
>> @@ -687,6 +690,17 @@ static void populate_value(struct ref_array_item *ref)
>>                         else
>>                                 v->s = " ";
>>                         continue;
>> +               } else if (starts_with(name, "align:")) {
>> +                       const char *valp = NULL;
>> +
>> +                       skip_prefix(name, "align:", &valp);
>> +                       if (!valp[0])
>> +                               die(_("no value given with 'align:'"));
>> +                       strtoul_ui(valp, 10, &ref->align_value);
>> +                       if (ref->align_value < 1)
>> +                               die(_("value should be greater than zero: align:%u"), ref->align_value);
>> +                       v->s = "";
>
> Mental note: v->s points at literal zero-length string ("").
>
>> +                       continue;
>>                 } else
>>                         continue;
>>
>> @@ -1254,17 +1268,40 @@ static void emit(const char *cp, const char *ep)
>>         }
>>  }
>>
>> +static void assign_formating(struct ref_array_item *ref, int parsed_atom, struct atom_value *v)
>> +{
>> +       if (ref->align_value && !starts_with(used_atom[parsed_atom], "align")) {
>> +               unsigned int len = 0;
>> +
>> +               if (*v->s)
>> +                       len = utf8_strwidth(v->s);
>> +               if (ref->align_value > len) {
>> +                       struct strbuf buf = STRBUF_INIT;
>> +                       if (*v->s)
>> +                               strbuf_addstr(&buf, v->s);
>> +                       if (*v->s && v->s[0] == '\0')
>> +                               free((char *)v->s);
>
> Is the "v->s[0] == '\0'" checking for the same literal zero-length
> string assigned above? If so, attempting to free() that string doesn't
> make sense, since it's not heap-allocated. Maybe you meant != '\0'?
>
> Overall, this code is getting rather complex and difficult to follow
> (especially with all the 'v->s' checks thrown in). Junio's proposed
> 'pseudo_atom' and 'ref_formatting_state' would go a long way toward
> simplifying it.
>