/usr/include/ is in liblog4cplus-dev 1.0.4-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/log4cplus/
/usr/include/log4cplus/syslogappender.h
/usr/include/log4cplus/spi/
/usr/include/log4cplus/spi/filter.h
/usr/include/log4cplus/spi/rootlogger.h
/usr/include/log4cplus/spi/objectregistry.h
/usr/include/log4cplus/spi/factory.h
/usr/include/log4cplus/spi/loggerfactory.h
/usr/include/log4cplus/spi/loggingevent.h
/usr/include/log4cplus/spi/loggerimpl.h
/usr/include/log4cplus/spi/appenderattachable.h
/usr/include/log4cplus/hierarchy.h
/usr/include/log4cplus/fstreams.h
/usr/include/log4cplus/ndc.h
/usr/include/log4cplus/loggingmacros.h
/usr/include/log4cplus/configurator.h
/usr/include/log4cplus/fileappender.h
/usr/include/log4cplus/streams.h
/usr/include/log4cplus/consoleappender.h
/usr/include/log4cplus/logger.h
/usr/include/log4cplus/helpers/
/usr/include/log4cplus/helpers/syncprims.h
/usr/include/log4cplus/helpers/appenderattachableimpl.h
/usr/include/log4cplus/helpers/property.h
/usr/include/log4cplus/helpers/pointer.h
/usr/include/log4cplus/helpers/socket.h
/usr/include/log4cplus/helpers/thread-config.h
/usr/include/log4cplus/helpers/timehelper.h
/usr/include/log4cplus/helpers/logloguser.h
/usr/include/log4cplus/helpers/syncprims-pthreads.h
/usr/include/log4cplus/helpers/threads.h
/usr/include/log4cplus/helpers/loglog.h
/usr/include/log4cplus/helpers/stringhelper.h
/usr/include/log4cplus/helpers/sleep.h
/usr/include/log4cplus/helpers/socketbuffer.h
/usr/include/log4cplus/config/
/usr/include/log4cplus/config/defines.hxx
/usr/include/log4cplus/appender.h
/usr/include/log4cplus/version.h
/usr/include/log4cplus/nullappender.h
/usr/include/log4cplus/socketappender.h
/usr/include/log4cplus/layout.h
/usr/include/log4cplus/loglevel.h
/usr/include/log4cplus/hierarchylocker.h
/usr/include/log4cplus/tstring.h
/usr/include/log4cplus/config.hxx