com/foo/config4.cpp

This file is a simpler example of how to use the current module name to select the Log4cxx configuration file.

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "config.h"
#include "product_version.h" // Provides getVendorFolder() and getProductFolder()
#include <log4cxx/logmanager.h>
#include <log4cxx/defaultconfigurator.h>
#include <log4cxx/basicconfigurator.h>
#include <log4cxx/helpers/transcoder.h>
#include <vector>
 
namespace com { namespace foo {
 
// Retrieve the \c name logger pointer.
// Configure Log4cxx on the first call.
auto getLogger(const std::string& name) -> LoggerPtr {
    using namespace log4cxx;
    static struct log4cxx_initializer {
        log4cxx_initializer() {
            auto vendorFolder = getVendorFolder();
            auto productFolder = getProductFolder();
            LOG4CXX_DECODE_CHAR(lsVendorFolder, vendorFolder);
            LOG4CXX_DECODE_CHAR(lsProductFolder, productFolder);
 
            // Allow expansion of ${CURRENT_VENDOR_FOLDER} and ${CURRENT_PRODUCT_FOLDER}
            // when loading a configuration from a file
            auto& props = spi::Configurator::properties();
#ifndef WIN32
            props.setProperty(LOG4CXX_STR("LocalAppData"), LOG4CXX_STR("/var/local"));
#endif
            props.setProperty(LOG4CXX_STR("CURRENT_VENDOR_FOLDER"), lsVendorFolder);
            props.setProperty(LOG4CXX_STR("CURRENT_PRODUCT_FOLDER"), lsProductFolder);
 
            // Check every 5 seconds for configuration file changes
            DefaultConfigurator::setConfigurationWatchSeconds(5);
 
            // Look for a configuration file in the current working directory
            // and the same directory as the program
            std::vector<LogString> paths
                { LOG4CXX_STR(".")
                , LOG4CXX_STR("${PROGRAM_FILE_PATH.PARENT_PATH}")
                };
            std::vector<LogString> names
                { LOG4CXX_STR("${PROGRAM_FILE_PATH.STEM}.xml")
                , LOG4CXX_STR("${PROGRAM_FILE_PATH.STEM}.properties")
                };
            auto status       = spi::ConfigurationStatus::NotConfigured;
            auto selectedPath = LogString();
            std::tie(status, selectedPath) = DefaultConfigurator::configureFromFile(paths, names);
            if (status == spi::ConfigurationStatus::NotConfigured)
                BasicConfigurator::configure(); // Send events to the console
        }
        ~log4cxx_initializer() {
            LogManager::shutdown();
        }
    } initialiser;
    return name.empty()
        ? LogManager::getRootLogger()
        : LogManager::getLogger(name);
}
 
} } // namespace com::foo