Log4cplus provides a port of the log4j logging framework for C++.

Log4cplus is a featureful log facility with various filters, run-time
re-configurations, and Wide Character (UNICODE) support.  It provides
log levels, hierarchal loggers, NDC (Nested Diagnostic Context),
and log rotation support. It can log to the console, files, syslog,
Windows events, or via sockets.