Re: [PATCH 13/46] qemu-option: Simplify around find_default_by_name()

[Markus Armbruster]

Eric Blake <eblake@redhat.com> writes:

> On 6/24/20 11:43 AM, Markus Armbruster wrote:
>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>> ---
>>   util/qemu-option.c | 13 ++++---------
>>   1 file changed, 4 insertions(+), 9 deletions(-)
>>
>> diff --git a/util/qemu-option.c b/util/qemu-option.c
>> index ddcf3072c5..d9293814b4 100644
>> --- a/util/qemu-option.c
>> +++ b/util/qemu-option.c
>> @@ -286,11 +286,9 @@ const char *qemu_opt_get(QemuOpts *opts, const char 
>> *name)
>>       opt = qemu_opt_find(opts, name);
>>       if (!opt) {
>>           def_val = find_default_by_name(opts, name);
>> -        if (def_val) {
>> -            return def_val;
>> -        }
>> +        return def_val;
>>       }
>> -    return opt ? opt->str : NULL;
>> +    return opt->str;
>>   }
>
> You could go with even fewer lines and variables by inverting the logic:
>
> if (opt) {
>     return opt->str;
> }
> return find_default_by_name(opts, name);

Yes, that's better.

>>     void qemu_opt_iter_init(QemuOptsIter *iter, QemuOpts *opts,
>> const char *name)
>> @@ -320,7 +318,7 @@ char *qemu_opt_get_del(QemuOpts *opts, const char *name)
>>   {
>>       QemuOpt *opt;
>>       const char *def_val;
>> -    char *str = NULL;
>> +    char *str;
>>         if (opts == NULL) {
>>           return NULL;
>> @@ -329,10 +327,7 @@ char *qemu_opt_get_del(QemuOpts *opts, const char *name)
>>       opt = qemu_opt_find(opts, name);
>>       if (!opt) {
>>           def_val = find_default_by_name(opts, name);
>> -        if (def_val) {
>> -            str = g_strdup(def_val);
>> -        }
>> -        return str;
>> +        return g_strdup(def_val);
>
> Similarly, you could drop def_val with:
>  return g_strdup(find_default_by_name(opts, name));

Your contracted version is still readable; sold.

> Either way,
> Reviewed-by: Eric Blake <eblake@redhat.com>

Thanks!