On 03/16/2010 08:22 PM, Andreas Huber wrote:
"Andrey Semashev" <andrey.semashev@gmail.com> wrote in message news:4B9FAFD5.50409@gmail.com...
If we go with method a), we'd need a way to enumerate all global loggers.
Not sure why would you need to enumerate loggers. You could simply specify all the channels in the filter, if their number is not very big.
Loggers are declared by thrird party code, so we have no idea about the number of loggers.
I see.
If it is, you can create your own function that accepts the channel name and then decides if it is enabled. This function can then be converted into a filter like this:
bool is_channel_enabled(std::string const& chan_name);
sink->set_filter( flt::attr< std::string >("Channel").satisfies(&is_channel_enabled) );
Ok, that will certainly work for us, but I'd consider this a (small) hack, because we'd have to duplicate information that is presumably already present in Boost.Log.
The loggers are not related to each other, so if some logger has a channel attribute, the library (the core, filters, etc.) won't know that until it starts emitting log records.
More precisely, we want to provide a utility function where you pass in a logger and a severity and the function then modifies the global filter so that all records comming from the specified logger with a severity below the specified one will be discarded.
But if you can pass a logger to this function, why can't you pass the channel name?
Unless I'm missing something, this would require us keeping a global list of all loggers that have a filter applied, correct?
Unless you can work with channel names instead of loggers, yes.
I assumed that somewhere Boost.Log keeps such a list anyway, so I'd rather use that one than build our own.
No, the library doesn't keep track of loggers.