Bug#714613: ap_log_perror ignores LogLevel configuration directives

[Stefan Fritsch <sf@sfritsch.de>]

On Monday 01 July 2013, Matthew Vernon wrote:
> Source: apache2
> Version: 2.4.4-6
> Severity: normal
> Tags: upstream
> 
> Hi,
> 
> This problem bit me while I was trying to debug merging
> configurations within an apache module. The interface you get is:
> 
> void *merge_dir_config(apr_pool_t *p, void* base, void *new)
> 
> so the only logging function you can use is ap_log_perror.

Since the server config does not yet exist at this stage, that is 
correct.


> ....which means that however you configure LogLevel, ap_log_perror
> won't result in anything being logged unless you set the level to
> <= ap_default_loglevel (which is APLOG_WARNING).
> 
> Since this is the only way to log the behaviour of config-merging
> code (which you'd naturally want to log at DEBUG or similar), I
> think this is a bug.

You can set ap_default_loglevel with the -e command line option. I 
guess this could be documented better. But to debug stuff 
before/during the first config parsing, this is is all you get.

There is also the possibility to use ap_log_error() with 
ap_server_conf as server_rec. But IIRC, this is not safe in 2.2, 
though. Maybe the behavior of ap_log_perror() can be improved to use 
the main server's loglevel after the config has been created, though. 
I will look at it when I have some time.