Question

最近我开始使用boost.log，并遇到一个问题，即如果抛出一个无法处理的异常，则不会将日志消息写入日志文件。我正在使用滚动文本文件并设置了自动闪光选项。

以下是来自样本的修改后的来源：

#include <stdexcept>
#include <string>
#include <iostream>
#include <fstream>
#include <functional>
#include <boost/ref.hpp>
#include <boost/bind.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/date_time/gregorian/gregorian.hpp>
#include <boost/date_time/posix_time/posix_time_types.hpp>
#include <boost/thread/thread.hpp>
#include <boost/thread/barrier.hpp>

#include <boost/log/common.hpp>
#include <boost/log/filters.hpp>
#include <boost/log/formatters.hpp>
#include <boost/log/attributes.hpp>
#include <boost/log/sinks.hpp>
#include <boost/log/utility/empty_deleter.hpp>
#include <boost/log/utility/record_ordering.hpp>

namespace logging = boost::log;
namespace attrs = boost::log::attributes;
namespace src = boost::log::sources;
namespace sinks = boost::log::sinks;
namespace fmt = boost::log::formatters;
namespace keywords = boost::log::keywords;

using boost::shared_ptr;
using namespace boost::gregorian;

enum
{
    LOG_RECORDS_TO_WRITE = 100,
    LOG_RECORDS_TO_WRITE_BEFORE_EXCEPTION = 10,
    THREAD_COUNT = 10

};

BOOST_LOG_DECLARE_GLOBAL_LOGGER(test_lg, src::logger_mt)

//! This function is executed in multiple threads
void thread_fun(boost::barrier& bar)
{
    // Wait until all threads are created
    bar.wait();

    // Here we go. First, identify the thread.
    BOOST_LOG_SCOPED_THREAD_TAG("ThreadID", boost::thread::id, boost::this_thread::get_id());

    // Now, do some logging
    for (unsigned int i = 0; i < LOG_RECORDS_TO_WRITE; ++i)
    {
        BOOST_LOG(get_test_lg()) << "Log record " << i;

        if(i > LOG_RECORDS_TO_WRITE_BEFORE_EXCEPTION)
        {
            BOOST_THROW_EXCEPTION(std::exception("unhandled exception"));
        }
    }

}

int main(int argc, char* argv[])
{
    try
    {
        typedef sinks::synchronous_sink< sinks::text_file_backend > file_sink;
        shared_ptr< file_sink > sink(new file_sink(
            keywords::file_name = L"%Y%m%d_%H%M%S_%5N.log",     // file name pattern
            keywords::rotation_size = 10 * 1024 * 1024,         // rotation size, in characters
            keywords::auto_flush = true                         // make each log record flushed to the file
            ));

        // Set up where the rotated files will be stored
        sink->locked_backend()->set_file_collector(sinks::file::make_collector(
            keywords::target = "log"             // where to store rotated files
            ));

        // Upon restart, scan the target directory for files matching the file_name pattern
        sink->locked_backend()->scan_for_files();

        sink->locked_backend()->set_formatter(
            fmt::format("%1%: [%2%] [%3%] - %4%")
            % fmt::attr< unsigned int >("Line #")
            % fmt::date_time< boost::posix_time::ptime >("TimeStamp")
            % fmt::attr< boost::thread::id >("ThreadID")
            % fmt::message()
            );

        // Add it to the core
        logging::core::get()->add_sink(sink);

        // Add some attributes too
        shared_ptr< logging::attribute > attr(new attrs::local_clock);
        logging::core::get()->add_global_attribute("TimeStamp", attr);
        attr.reset(new attrs::counter< unsigned int >);
        logging::core::get()->add_global_attribute("Line #", attr);

        // Create logging threads
        boost::barrier bar(THREAD_COUNT);
        boost::thread_group threads;
        for (unsigned int i = 0; i < THREAD_COUNT; ++i)
            threads.create_thread(boost::bind(&thread_fun, boost::ref(bar)));

        // Wait until all action ends
        threads.join_all();

        return 0;
    }
    catch (std::exception& e)
    {
        std::cout << "FAILURE: " << e.what() << std::endl;
        return 1;
    }
}

Source是在Visual Studio 2008下编译的.prost.log编译为boost 1.40。

非常感谢任何帮助。

Answer 1

检查日志文件是否在进程的当前工作目录中，而不是指定的文件收集器目标目录（示例代码中的“log”）。此外，您可能希望为接收器“file_name”模式指定目录。

正如“JQ”所指出的那样，不要期望在异常后看到任何记录。

应用程序崩溃时，不会存储boost.log auto_flush文件

1 个答案: