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/*
* Copyright Andrey Semashev 2007 - 2014.
* 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)
*/
/*!
* \file main.cpp
* \author Andrey Semashev
* \date 12.05.2010
*
* \brief An example of initializing the library from a settings file,
* with a custom formatter for an attribute.
*/
// #define BOOST_ALL_DYN_LINK 1
#include <string>
#include <iostream>
#include <fstream>
#include <stdexcept>
#include <boost/ref.hpp>
#include <boost/bind.hpp>
#include <boost/smart_ptr/make_shared_object.hpp>
#include <boost/log/core.hpp>
#include <boost/log/common.hpp>
#include <boost/log/attributes.hpp>
#include <boost/log/core/record.hpp>
#include <boost/log/attributes/value_visitation.hpp>
#include <boost/log/utility/setup/from_stream.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/utility/setup/formatter_parser.hpp>
namespace logging = boost::log;
namespace attrs = boost::log::attributes;
namespace src = boost::log::sources;
enum severity_level
{
normal,
notification,
warning,
error,
critical
};
BOOST_LOG_INLINE_GLOBAL_LOGGER_DEFAULT(test_lg, src::severity_logger< >)
//! Our custom formatter for the scope list
struct scope_list_formatter
{
typedef void result_type;
typedef attrs::named_scope::value_type scope_stack;
explicit scope_list_formatter(logging::attribute_name const& name) :
name_(name)
{
}
void operator()(logging::record_view const& rec, logging::formatting_ostream& strm) const
{
// We need to acquire the attribute value from the log record
logging::visit< scope_stack >
(
name_,
rec.attribute_values(),
boost::bind(&scope_list_formatter::format, _1, boost::ref(strm))
);
}
private:
//! This is where our custom formatting takes place
static void format(scope_stack const& scopes, logging::formatting_ostream& strm)
{
scope_stack::const_iterator it = scopes.begin(), end = scopes.end();
for (; it != end; ++it)
{
strm << "\t" << it->scope_name << " [" << it->file_name << ":" << it->line << "]\n";
}
}
private:
logging::attribute_name name_;
};
class my_scopes_formatter_factory :
public logging::formatter_factory< char >
{
public:
/*!
* This function creates a formatter for the MyScopes attribute.
* It effectively associates the attribute with the scope_list_formatter class
*/
formatter_type create_formatter(
logging::attribute_name const& attr_name, args_map const& args)
{
return formatter_type(scope_list_formatter(attr_name));
}
};
//! The function initializes the logging library
void init_logging()
{
// First thing - register the custom formatter for MyScopes
logging::register_formatter_factory("MyScopes", boost::make_shared< my_scopes_formatter_factory >());
// Then load the settings from the file
std::ifstream settings("settings.txt");
if (!settings.is_open())
throw std::runtime_error("Could not open settings.txt file");
logging::init_from_stream(settings);
// Add some attributes
logging::add_common_attributes();
logging::core::get()->add_global_attribute("MyScopes", attrs::named_scope());
}
//! The function tests logging
void try_logging()
{
BOOST_LOG_FUNCTION();
src::severity_logger< >& lg = test_lg::get();
BOOST_LOG_SEV(lg, critical) << "This is a critical severity record";
BOOST_LOG_NAMED_SCOPE("random name");
BOOST_LOG_SEV(lg, error) << "This is a error severity record";
}
int main(int argc, char* argv[])
{
try
{
init_logging();
try_logging();
}
catch (std::exception& e)
{
std::cout << "FAILURE: " << e.what() << std::endl;
return -1;
}
return 0;
}
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