Search code examples
c++boostboost-log

Boost Log causes crash when trying first log statement (when not Administrator)

I am trying to deploy my application right now, which uses Boost Log (Boost 1.58). It is a simple console app, being run in Windows 7. Logging works perfectly fine on my personal desktop.

However, when I deploy the application to a Win7 virtual machine, it crashes upon my first log statement:

boost::log::sources::severity_logger<SeverityLevel> slg;
BOOST_LOG_SEV(slg, SeverityLevel::Notification) << L"Application loaded"; // <-- Crash here

The log directory gets created, but the log file never gets created and the application crashes.

I have tried a logfile directory in my %APPDATA% directory, and also in my My Documents directory.

The odd thing is: When I run the app as Administrator, it works!

So this must be a permissions thing, but I have permissions to these folders, so...

Any ideas?

* MORE *

Here is the code to set up my logger:

    wstring appData = GetMyAppDataPath();
    boost::shared_ptr< boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend > > textFileSink(new boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend >(to store rotated files
        boost::log::keywords::file_name = "log_%7N.log",                // file name pattern
        boost::log::keywords::rotation_size = 16384                     // rotation size, in characters
        ));
    // Set up where the rotated files will be stored
    textFileSink->locked_backend()->set_file_collector(boost::log::sinks::file::make_collector(
        boost::log::keywords::target = appData + L"\\logs",         // where to store rotated files
        boost::log::keywords::max_size = 64 * 1024 * 1024,              // maximum total size of the stored files, in bytes (64 MiB)
        boost::log::keywords::min_free_space = 100 * 1024 * 1024        // minimum free space on the drive, in bytes
        ));
    // Upon restart, scan the target directory for files matching the file_name pattern
    textFileSink->locked_backend()->scan_for_files();
    // Set up the format for output to the text file.
    textFileSink->set_formatter(boost::log::expressions::stream
        << "[" << boost::log::expressions::attr< boost::posix_time::ptime >("TimeStamp") 
        << " " << boost::log::expressions::attr< SeverityLevel, severity_tag >("Severity") << "] "
        << boost::log::expressions::message
        );
    // Add it to the core
    boost::log::core::get()->add_sink(textFileSink);

which is mostly taken from here: http://www.boost.org/doc/libs/1_58_0/libs/log/example/rotating_file/main.cpp .

* ALSO *

I added an exception handler to the Boost Logger by adding: 

boost::log::core::get()->set_exception_handler(boost::log::make_exception_handler<
        std::runtime_error,
        std::logic_error,
        std::exception
    >(pbb_boost_log_exception_handler()));

And then adding the handler. When I then run, I am able to catch the following exception before the crash:

std::exception: Failed to open file for writing: Input/output error: "C:\Program Files\My App\log_0000000.log"

WTF? I am definitely setting the log file location to the appData value, which I have verified is correct. Furthermore, if I run this app as administrator, the log file ends up in the place where I expect it (appdata folder). So it must just be creating a temporary file at the executable's location. Is this normal behavior? I can't imagine it is... so what did I do??

Solution

  • Okay, I figured it out.

    The issue was this line here, setting up the text backend:

    boost::shared_ptr< boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend > > textFileSink(new boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend >
    boost::log::keywords::file_name = "log_%7N.log",                // file name pattern
    boost::log::keywords::rotation_size = 16384                     // rotation size, in characters
    ));

    There was definitely a temporary log file being written to the local directory (a Program Files directory, which is bad). Based on the documentation here, I saw that there is a temporary file written, and then passed to the file collector.

    So for the solution, I changed the code to this: 

    boost::shared_ptr< boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend > > textFileSink(new boost::log::sinks::synchronous_sink< boost::log::sinks::text_file_backend >(
    boost::log::keywords::file_name = appData + L"\\log_%7N.log",   // file name pattern
    boost::log::keywords::rotation_size = 16384                         // rotation size, in characters
    ));

    Notice that I am now specifying the file_name as being in the AppData directory instead.

    This solved the problem.

    I have a hard time believing that I am the first one to run into this issue, but I could not find this anywhere on the web. This would be a commonly recurring problem for windows developers, so hopefully this is helpful to someone else.