[log4perl-devel] Does $Log::Log4perl::caller_depth work with logdie?

[Adrian I. <adr...@ho...>]

Hi,

As far as I can tell it doesn't. I use Log4Perl via a wrapper and have found 
that my logdies are reported as occurring in my wrapper rather than in the 
code calling the wrapper. This is despite my setting 
$Log::Log4perl::caller_depth = 1 in the package defining my wrapper.

The first reason I think the problem lies in the Log4Perl code and not my 
own is that I searched for caller_depth in the Log4Perl code and while there 
are a number of places it's changed, it only seems to be used in the 
Log::Log4perl::Layout::PatternLayout::render subroutine which isn't involved 
in the implementation of logdie.

After some further investigation I think the problem is in the 
Log4Perl::Logger module. In particular the callerline subroutine. I've 
attached a diff for Logger.pm that fixes the problem which works as follows:
i) Keep stepping up the call-stack until you've reached caller_depth steps 
out of the current file.
ii) Don't evaluate the call stack if it's not needed for the message
iii) Avoid a uninitialized warning from the 'at $file line $line' in the 
case where the caller_depth has been set too large.

Points (ii) and (iii) don't actually fix the problem at hand but, in my 
opinion, do improve things slightly . Potentially (iii) could be implemented 
better (i.e. print a warning about caller_depth being wrong, allowing the 
thread id to be added to the message even if we've failed with $file etc) 
but that's up to you :o)

Cheers,
Adrian

NB I'm using 'Log-Log4perl' version 1.05 in ActivePerl 5.8.4.810. I know 
1.08 is available but I'm using Windows XP and 1.05 is the latest available 
via ppm.
NNB I had a look at the release notes between 1.05 and 1.08 and couldn't see 
any mention of something fixing this problem .