boost log to print source code file name and line number

As Horus pointed out, you can use attributes to log file and line numbers. However it is best to avoid using multi-statements macros to avoid problems with expressions like this:

if (something)
   LOG_FILE_LINE(debug) << "It's true"; // Only the first statement is conditional!

You can do better creating a macro that leverages the underlying behavior of the Boost Log library. For example, BOOST_LOG_SEV is:

#define BOOST_LOG_SEV(logger, lvl) BOOST_LOG_STREAM_SEV(logger, lvl)
#define BOOST_LOG_STREAM_SEV(logger, lvl)\
    BOOST_LOG_STREAM_WITH_PARAMS((logger), (::boost::log::keywords::severity = (lvl)))

Using BOOST_LOG_STREAM_WITH_PARAMS you can set and get more attributes, like this:

// New macro that includes severity, filename and line number
#define CUSTOM_LOG(logger, sev) \
   BOOST_LOG_STREAM_WITH_PARAMS( \
      (logger), \
         (set_get_attrib("File", path_to_filename(__FILE__))) \
         (set_get_attrib("Line", __LINE__)) \
         (::boost::log::keywords::severity = (boost::log::trivial::sev)) \
   )

// Set attribute and return the new value
template<typename ValueType>
ValueType set_get_attrib(const char* name, ValueType value) {
   auto attr = logging::attribute_cast<attrs::mutable_constant<ValueType>>(logging::core::get()->get_thread_attributes()[name]);
   attr.set(value);
   return attr.get();
}

// Convert file path to only the filename
std::string path_to_filename(std::string path) {
   return path.substr(path.find_last_of("/\\")+1);
}

The complete source code is:

#include <boost/log/trivial.hpp>
#include <boost/log/sources/severity_logger.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/log/utility/setup/console.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/attributes/mutable_constant.hpp>
#include <boost/date_time/posix_time/posix_time_types.hpp>
#include <boost/log/support/date_time.hpp>
#include <boost/log/attributes/mutable_constant.hpp>

namespace logging  = boost::log;
namespace attrs    = boost::log::attributes;
namespace expr     = boost::log::expressions;
namespace src      = boost::log::sources;
namespace keywords = boost::log::keywords;

// New macro that includes severity, filename and line number
#define CUSTOM_LOG(logger, sev) \
   BOOST_LOG_STREAM_WITH_PARAMS( \
      (logger), \
         (set_get_attrib("File", path_to_filename(__FILE__))) \
         (set_get_attrib("Line", __LINE__)) \
         (::boost::log::keywords::severity = (boost::log::trivial::sev)) \
   )

// Set attribute and return the new value
template<typename ValueType>
ValueType set_get_attrib(const char* name, ValueType value) {
   auto attr = logging::attribute_cast<attrs::mutable_constant<ValueType>>(logging::core::get()->get_thread_attributes()[name]);
   attr.set(value);
   return attr.get();
}

// Convert file path to only the filename
std::string path_to_filename(std::string path) {
   return path.substr(path.find_last_of("/\\")+1);
}

void init() {
   // New attributes that hold filename and line number
   logging::core::get()->add_thread_attribute("File", attrs::mutable_constant<std::string>(""));
   logging::core::get()->add_thread_attribute("Line", attrs::mutable_constant<int>(0));

   logging::add_file_log (
    keywords::file_name = "sample.log",
    keywords::format = (
     expr::stream
      << expr::format_date_time<boost::posix_time::ptime>("TimeStamp", "%Y-%m-%d_%H:%M:%S.%f")
      << ": <" << boost::log::trivial::severity << "> "
      << '['   << expr::attr<std::string>("File")
               << ':' << expr::attr<int>("Line") << "] "
      << expr::smessage
    )
   );
   logging::add_common_attributes();
}

int main(int argc, char* argv[]) {
   init();
   src::severity_logger<logging::trivial::severity_level> lg;

   CUSTOM_LOG(lg, debug) << "A regular message";
   return 0;
}

This generate a log like this:

2015-10-15_15:25:12.743153: <debug> [main.cpp:61] A regular message

As user2943014 pointed out, using scopes prints the line number where you opened that scope, not the line number where you emitted a log message using BOOST_LOG_SEV.

You can use attributes to log the line numbers etc at the place you actually logged.

Register global attributes in your logging initialization function:

using namespace boost::log;
core::get()->add_global_attribute("Line", attributes::mutable_constant<int>(5));
core::get()->add_global_attribute("File", attributes::mutable_constant<std::string>(""));
core::get()->add_global_attribute("Function", attributes::mutable_constant<std::string>(""));

Setting these attributes in your logging macro:

#define logInfo(methodname, message)                          \
  LOG_LOCATION;                                               \
  BOOST_LOG_SEV(_log, boost::log::trivial::severity_level::trace) << message

#define LOG_LOCATION                            \
  boost::log::attribute_cast<boost::log::attributes::mutable_constant<int>>(boost::log::core::get()->get_global_attributes()["Line"]).set(__LINE__); \
  boost::log::attribute_cast<boost::log::attributes::mutable_constant<std::string>>(boost::log::core::get()->get_global_attributes()["File"]).set(__FILE__); \
  boost::log::attribute_cast<boost::log::attributes::mutable_constant<std::string>>(boost::log::core::get()->get_global_attributes()["Function"]).set(__func__);

Not exactly beautiful, but it works and it was a long way for me. It's a pity boost doesn't offer this feature out of the box.