[FFmpeg-devel] [PATCH] provide AV_BASE64_SIZE() macro

[Howard Chu]

Michael Niedermayer wrote:
> On Thu, Jun 03, 2010 at 05:47:05PM -0700, Howard Chu wrote:
>> M?ns Rullg?rd wrote:
>>> Michael Niedermayer<michaelni at gmx.at>   writes:
>>>
>>>> On Thu, Jun 03, 2010 at 11:00:49PM +0100, M?ns Rullg?rd wrote:
>>>>> Michael Niedermayer<michaelni at gmx.at>   writes:
>>>>>
>>>>>> On Thu, Jun 03, 2010 at 10:39:52PM +0100, M?ns Rullg?rd wrote:
>>>>>>> Michael Niedermayer<michaelni at gmx.at>   writes:
>>>>>>>
>>>>>>>> On Thu, Jun 03, 2010 at 01:50:06PM -0700, Howard Chu wrote:
>>>>>>>>> Just for convenience...
>>>>>>>>
>>>>>>>> IMHO this is making the code harder to understand
>>>>>>>
>>>>>>> How so?  It's an obscure calculation repeated multiple times.  That is
>>>>>>> exactly the kind of situation functions and macros were invented for.
>>>>>>
>>>>>> to me the calculation is clear,
>>>>>
>>>>> Because you happen to know exactly how base64 encoding works.  This is
>>>>> IMO not a reasonable requirement to place on users of the interface.
>>>>
>>>> its documented though, and i think its reasonable to expect users
>>>> to read the dox of what they use.
>>>
>>> By extension, one could argue that the base64 encoding is documented,
>>> wherefore we don't need to provide a function for it.
>>>
>>> I think a macro like this is good for the same reasons we have FFMAX
>>> and similar macros.
>>>
>>>>> Besides, the same rather complex calculation repeated numerous times
>>>>> is a recipe for trouble.  Sooner or later, someone will get it wrong
>>>>> in one place.  Then people will copy it from there, and the error will
>>>>> spread.  It's much better to put it all in a macro.
>>>>
>>>> i dont really see this as a big issue but if people prefer then iam not
>>>> against the macro
>>
>> So, OK to commit, with the fixed comment?
>>
>> +/**
>> + * Calculate the output size needed to base64-encode x bytes.
>> + */
>
> ok if it makes people happy

Done. Wasn't sure if it was OK as a single commit, so split in two. One to 
define the macro, one to use it.

-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/