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/*
* Copyright Andrey Semashev 2007 - 2015.
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*/
#include <cstddef>
#include <string>
#include <fstream>
#include <iostream>
#include <stdexcept>
#include <boost/smart_ptr/shared_ptr.hpp>
#include <boost/smart_ptr/make_shared_object.hpp>
#include <boost/thread/shared_mutex.hpp>
#include <boost/log/core.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/sources/basic_logger.hpp>
#include <boost/log/sources/severity_feature.hpp>
#include <boost/log/sources/exception_handler_feature.hpp>
#include <boost/log/sources/features.hpp>
#include <boost/log/sources/record_ostream.hpp>
#include <boost/log/sources/global_logger_storage.hpp>
#include <boost/log/sinks/sync_frontend.hpp>
#include <boost/log/sinks/text_ostream_backend.hpp>
#include <boost/log/attributes/scoped_attribute.hpp>
#include <boost/log/utility/exception_handler.hpp>
namespace logging = boost::log;
namespace src = boost::log::sources;
namespace expr = boost::log::expressions;
namespace sinks = boost::log::sinks;
namespace attrs = boost::log::attributes;
namespace keywords = boost::log::keywords;
//[ example_sources_exception_handler
enum severity_level
{
normal,
warning,
error
};
// A logger class that allows to intercept exceptions and supports severity level
class my_logger_mt :
public src::basic_composite_logger<
char,
my_logger_mt,
src::multi_thread_model< boost::shared_mutex >,
src::features<
src::severity< severity_level >,
src::exception_handler
>
>
{
BOOST_LOG_FORWARD_LOGGER_MEMBERS(my_logger_mt)
};
BOOST_LOG_INLINE_GLOBAL_LOGGER_INIT(my_logger, my_logger_mt)
{
my_logger_mt lg;
// Set up exception handler: all exceptions that occur while
// logging through this logger, will be suppressed
lg.set_exception_handler(logging::make_exception_suppressor());
return lg;
}
void logging_function()
{
// This will not throw
BOOST_LOG_SEV(my_logger::get(), normal) << "Hello, world";
}
//]
//[ example_utility_exception_handler
struct my_handler
{
typedef void result_type;
void operator() (std::runtime_error const& e) const
{
std::cout << "std::runtime_error: " << e.what() << std::endl;
}
void operator() (std::logic_error const& e) const
{
std::cout << "std::logic_error: " << e.what() << std::endl;
throw;
}
};
void init_exception_handler()
{
// Setup a global exception handler that will call my_handler::operator()
// for the specified exception types
logging::core::get()->set_exception_handler(logging::make_exception_handler<
std::runtime_error,
std::logic_error
>(my_handler()));
}
//]
//[ example_utility_exception_handler_nothrow
struct my_handler_nothrow
{
typedef void result_type;
void operator() (std::runtime_error const& e) const
{
std::cout << "std::runtime_error: " << e.what() << std::endl;
}
void operator() (std::logic_error const& e) const
{
std::cout << "std::logic_error: " << e.what() << std::endl;
throw;
}
void operator() () const
{
std::cout << "unknown exception" << std::endl;
}
};
void init_exception_handler_nothrow()
{
// Setup a global exception handler that will call my_handler::operator()
// for the specified exception types. Note the std::nothrow argument that
// specifies that all other exceptions should also be passed to the functor.
logging::core::get()->set_exception_handler(logging::make_exception_handler<
std::runtime_error,
std::logic_error
>(my_handler_nothrow(), std::nothrow));
}
//]
void init()
{
typedef sinks::synchronous_sink< sinks::text_ostream_backend > text_sink;
boost::shared_ptr< text_sink > sink = boost::make_shared< text_sink >();
sink->locked_backend()->add_stream(
boost::make_shared< std::ofstream >("sample.log"));
sink->set_formatter
(
expr::stream
<< expr::attr< unsigned int >("LineID").or_throw() // this attribute will not be found, which will cause an exception
<< ": <" << expr::attr< severity_level >("Severity")
<< "> " << expr::smessage
);
logging::core::get()->add_sink(sink);
init_exception_handler();
}
int main(int, char*[])
{
init();
logging_function();
return 0;
}
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