[pulseaudio-discuss] Logging startup of the first instance...

[David Henningsson]

On 06/28/2012 09:41 AM, rong deng wrote:
> Hi David,
>
> I've come up with an idea to accommodate this situation, tell me if
> it's useful for you or there's a better solution. :)

I think this solution (to go with .1, .2 etc prefix) is good enough for me.
A question about the implementation though - is it racy? I'm not 
completely sure if two clients which in parallel try to spawn the 
server, end up choosing the same file name.

Would opening with O_EXCL work as a test instead, perhaps?

>
> So I've added a new syntax when we specified the file log target. The
> original one is file:<PATH>, now it's newfile:<PATH>.  This syntax
> would:
> 1. check if PATH file exists or not, if it doesn't exist, then
> everything is OK, we're not overriding anything, we do the original
> code route.
> 2. now unfortunately this file exists, then we try PATH.1, PATH.2,
> PATH.3 .... until we find a non-existent file, let's say it's PATH.5,
> so we create the PATH.5 as our log file target.
>
> Any comments are welcome.
>
> The patch is attached.
>
> 2012/6/11 David Henningsson <david.henningsson at canonical.com>:
>> On 06/11/2012 02:35 AM, rong deng wrote:
>>>
>>> 2012/6/4 David Henningsson<david.henningsson at canonical.com>:
>>>>
>>>> Sometimes I have users who complain about some problem, but after a
>>>> "pulseaudio -k" the problem is gone. Therefore asking them to restart
>>>> pulseaudio with -vvvv switch will not give any information about the
>>>> error.
>>>>
>>>>   * I could log to syslog (the default), but once I enable debug level
>>>> log,
>>>> the syslog daemon can start to ratelimit, especially during the startup
>>>> phase of pulseaudio.
>>>>
>>>>   * I could log to file, but then that file would quickly get overwritten,
>>>> as
>>>> soon as pulseaudio restarts.
>>>>
>>>> Is there a trick I'm missing here? Or would it be possible to add some
>>>> kind
>>>> of expansion to the log file name to make the files unique?
>>>
>>>
>>> Hi David,
>>>
>>> I'm doing the GSoC to enhance the logging functionality in pulseaudio,
>>> I could take a look at this issue and try to improve it a little bit.
>>> :)
>>
>>
>> Yes, I was actually thinking the same :-) Thanks!
>>
>> Not sure how to do it in the best way though. I'm figuring that at least a
>> timestamp and pid should be possible to insert into the log file name in a
>> configurable way.
>> Also we probably don't want to reinvent the wheel but use the expansion
>> mechanisms provided by ...something around us, or some library we're already
>> depending on, if we can find anything of use?
>> Maybe someone else knows more on the topic.
>>
>>
>> --
>> David Henningsson, Canonical Ltd.
>> https://launchpad.net/~diwic



-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic