On 06/10/2021 19:02, Andrew Gregory wrote:
> On 10/05/21 at 06:53pm, Morgan Adamiec wrote:
>>
>>
>> On 05/10/2021 18:49, Morgan Adamiec wrote:
>>>
>>>
>>> On 05/10/2021 18:10, Andrew Gregory wrote:
>>>> On 10/05/21 at 12:53pm, Morgan Adamiec wrote:
>>>>> On 4 Oct 2021 8:28 pm, Andrew Gregory <[email protected]>
>>>>> wrote:
>>>>>
>>>>>
>>>>> On 10/04/21 at 08:09pm, morganamilo wrote:
>>>>>
>>>>> > This is the error value generally used and the calling function
>>>>>
>>>>> > explicitly checks for -1, later causing the error to be missed
>>>>>
>>>>> > and the transaction to continue.
>>>>>
>>>>>
>>>>>
>>>>> This result is not compared to -1, the result of download_files is.
>>>>> If
>>>>> we want
>>>>>
>>>>> to guarantee that download_files will return -1 on error, that's
>>>>> where
>>>>> the
>>>>>
>>>>> return should be normalized, not in find_dl_candidates. Tying the
>>>>> API
>>>>> of one
>>>>>
>>>>> function to another like this is just going to cause confusion and
>>>>>
>>>>> breakage
>>>>>
>>>>> when somebody forgets in the future. Really, the caller of
>>>>>
>>>>> download_files
>>>>>
>>>>> should just check for a successful return; we return 1 as an error
>>>>> from
>>>>> lots of
>>>>>
>>>>> functions.
>>>>>
>>>>>
>>>>>
>>>>> I'll change that too. This should still be accepted though.
>>>>>
>>>>
>>>> Why? If your reasoning is just that -1 is a better error value, we use 1
>>>> in
>>>> lots of other places like I said and I don't want to change that one at a
>>>> time.
>>>>
>>>> $ grep 'return 1;' lib/libalpm/*.c src/*/*.c | wc -l
>>>>
>>>>
>>>> [0][1016]
>>>> 132
>>>>
>>>
>>> Everywhere in the function returns -1. Lets at least be consistent for
>>> the same function.
>>>
>>
>> Not to mention download_files returns 1 on everything up to date so 1 is
>> not an error in this case.
>
> find_dl_candidates, the function you are modifying, only return 0 or 1.
No it returns -1 on error except for that one error where it returns 1
instead. I'm not disagreeing with you, I'm just saying lets me
consistent and also fix this.
The
> problem is in download_files because it does not guarantee its own return
> value: it's not returning 0 on success/-1 on error, it's returning <whatever
> the functions it calls return>. Somebody modifying those functions in the
> future will have a hard time understanding the significance of their return
> values because they have to check not just the function calling them
> (download_files), but also the function calling download_files. That's a good
> recipe for confusion and exactly this kind of bug in the future. However you
> want to fix this, it should be clear from looking at download_files what the
> significance of find_dl_candidates' return value is.
>
> apg
>
